The Tor Browser: layout/tables/nsTableRowGroupFrame.cpp@44a2da4a2ab2 (annotated)

layout/tables/nsTableRowGroupFrame.cpp@44a2da4a2ab2 (annotated)

layout/tables/nsTableRowGroupFrame.cpp

Fri, 16 Jan 2015 04:50:19 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Fri, 16 Jan 2015 04:50:19 +0100
branch: TOR_BUG_9701
changeset 13: 44a2da4a2ab2
permissions: -rw-r--r--

Replace accessor implementation with direct member state manipulation, by
request https://trac.torproject.org/projects/tor/ticket/9701#comment:32

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "nsCOMPtr.h"
 #include "nsTableRowGroupFrame.h"
 #include "nsTableRowFrame.h"
 #include "nsTableFrame.h"
 #include "nsTableCellFrame.h"
 #include "nsPresContext.h"
 #include "nsStyleContext.h"
 #include "nsStyleConsts.h"
 #include "nsIContent.h"
 #include "nsGkAtoms.h"
 #include "nsIPresShell.h"
 #include "nsCSSRendering.h"
 #include "nsHTMLParts.h"
 #include "nsCSSFrameConstructor.h"
 #include "nsDisplayList.h"
 #include "nsCellMap.h"//table cell navigation
 #include <algorithm>
 using namespace mozilla;
 using namespace mozilla::layout;
 nsTableRowGroupFrame::nsTableRowGroupFrame(nsStyleContext* aContext):
   nsContainerFrame(aContext)
 {
   SetRepeatable(false);
 }
 nsTableRowGroupFrame::~nsTableRowGroupFrame()
 {
 }
 void
 nsTableRowGroupFrame::DestroyFrom(nsIFrame* aDestructRoot)
 {
   if (GetStateBits() & NS_FRAME_CAN_HAVE_ABSPOS_CHILDREN) {
     nsTableFrame::UnregisterPositionedTablePart(this, aDestructRoot);
   }
   nsContainerFrame::DestroyFrom(aDestructRoot);
 }
 NS_QUERYFRAME_HEAD(nsTableRowGroupFrame)
   NS_QUERYFRAME_ENTRY(nsTableRowGroupFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
 int32_t
 nsTableRowGroupFrame::GetRowCount()
 {
 #ifdef DEBUG
   for (nsFrameList::Enumerator e(mFrames); !e.AtEnd(); e.Next()) {
     NS_ASSERTION(e.get()->StyleDisplay()->mDisplay ==
                    NS_STYLE_DISPLAY_TABLE_ROW,
                  "Unexpected display");
     NS_ASSERTION(e.get()->GetType() == nsGkAtoms::tableRowFrame,
                  "Unexpected frame type");
   }
 #endif
   return mFrames.GetLength();
 }
 int32_t nsTableRowGroupFrame::GetStartRowIndex()
 {
   int32_t result = -1;
   if (mFrames.NotEmpty()) {
     NS_ASSERTION(mFrames.FirstChild()->GetType() == nsGkAtoms::tableRowFrame,
                  "Unexpected frame type");
     result = static_cast<nsTableRowFrame*>(mFrames.FirstChild())->GetRowIndex();
   }
   // if the row group doesn't have any children, get it the hard way
   if (-1 == result) {
     nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
     return tableFrame->GetStartRowIndex(this);
   }
   return result;
 }
 void  nsTableRowGroupFrame::AdjustRowIndices(int32_t aRowIndex,
                                              int32_t anAdjustment)
 {
   nsIFrame* rowFrame = GetFirstPrincipalChild();
   for ( ; rowFrame; rowFrame = rowFrame->GetNextSibling()) {
     if (NS_STYLE_DISPLAY_TABLE_ROW==rowFrame->StyleDisplay()->mDisplay) {
       int32_t index = ((nsTableRowFrame*)rowFrame)->GetRowIndex();
       if (index >= aRowIndex)
         ((nsTableRowFrame *)rowFrame)->SetRowIndex(index+anAdjustment);
     }
   }
 }
 nsresult
 nsTableRowGroupFrame::InitRepeatedFrame(nsPresContext*        aPresContext,
                                         nsTableRowGroupFrame* aHeaderFooterFrame)
 {
   nsTableRowFrame* copyRowFrame = GetFirstRow();
   nsTableRowFrame* originalRowFrame = aHeaderFooterFrame->GetFirstRow();
   AddStateBits(NS_REPEATED_ROW_OR_ROWGROUP);
   while (copyRowFrame && originalRowFrame) {
     copyRowFrame->AddStateBits(NS_REPEATED_ROW_OR_ROWGROUP);
     int rowIndex = originalRowFrame->GetRowIndex();
     copyRowFrame->SetRowIndex(rowIndex);
     // For each table cell frame set its column index
     nsTableCellFrame* originalCellFrame = originalRowFrame->GetFirstCell();
     nsTableCellFrame* copyCellFrame     = copyRowFrame->GetFirstCell();
     while (copyCellFrame && originalCellFrame) {
       NS_ASSERTION(originalCellFrame->GetContent() == copyCellFrame->GetContent(),
                    "cell frames have different content");
       int32_t colIndex;
       originalCellFrame->GetColIndex(colIndex);
       copyCellFrame->SetColIndex(colIndex);
       // Move to the next cell frame
       copyCellFrame     = copyCellFrame->GetNextCell();
       originalCellFrame = originalCellFrame->GetNextCell();
     }
     // Move to the next row frame
     originalRowFrame = originalRowFrame->GetNextRow();
     copyRowFrame = copyRowFrame->GetNextRow();
   }
   return NS_OK;
 }
 /**
  * We need a custom display item for table row backgrounds. This is only used
  * when the table row is the root of a stacking context (e.g., has 'opacity').
  * Table row backgrounds can extend beyond the row frame bounds, when
  * the row contains row-spanning cells.
  */
 class nsDisplayTableRowGroupBackground : public nsDisplayTableItem {
 public:
   nsDisplayTableRowGroupBackground(nsDisplayListBuilder* aBuilder,
                                    nsTableRowGroupFrame* aFrame) :
     nsDisplayTableItem(aBuilder, aFrame) {
     MOZ_COUNT_CTOR(nsDisplayTableRowGroupBackground);
   }
 #ifdef NS_BUILD_REFCNT_LOGGING
   virtual ~nsDisplayTableRowGroupBackground() {
     MOZ_COUNT_DTOR(nsDisplayTableRowGroupBackground);
   }
 #endif
   virtual void ComputeInvalidationRegion(nsDisplayListBuilder* aBuilder,
                                          const nsDisplayItemGeometry* aGeometry,
                                          nsRegion *aInvalidRegion) MOZ_OVERRIDE;
   virtual void Paint(nsDisplayListBuilder* aBuilder,
                      nsRenderingContext* aCtx) MOZ_OVERRIDE;
   NS_DISPLAY_DECL_NAME("TableRowGroupBackground", TYPE_TABLE_ROW_GROUP_BACKGROUND)
 };
 void
 nsDisplayTableRowGroupBackground::ComputeInvalidationRegion(nsDisplayListBuilder* aBuilder,
                                                             const nsDisplayItemGeometry* aGeometry,
                                                             nsRegion *aInvalidRegion)
 {
   if (aBuilder->ShouldSyncDecodeImages()) {
     if (nsTableFrame::AnyTablePartHasUndecodedBackgroundImage(mFrame, mFrame->GetNextSibling())) {
       bool snap;
       aInvalidRegion->Or(*aInvalidRegion, GetBounds(aBuilder, &snap));
     }
   }
   nsDisplayTableItem::ComputeInvalidationRegion(aBuilder, aGeometry, aInvalidRegion);
 }
 void
 nsDisplayTableRowGroupBackground::Paint(nsDisplayListBuilder* aBuilder,
                                         nsRenderingContext* aCtx)
 {
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(mFrame);
   TableBackgroundPainter painter(tableFrame,
                                  TableBackgroundPainter::eOrigin_TableRowGroup,
                                  mFrame->PresContext(), *aCtx,
                                  mVisibleRect, ToReferenceFrame(),
                                  aBuilder->GetBackgroundPaintFlags());
   painter.PaintRowGroup(static_cast<nsTableRowGroupFrame*>(mFrame));
 }
 // Handle the child-traversal part of DisplayGenericTablePart
 static void
 DisplayRows(nsDisplayListBuilder* aBuilder, nsFrame* aFrame,
             const nsRect& aDirtyRect, const nsDisplayListSet& aLists)
 {
   nscoord overflowAbove;
   nsTableRowGroupFrame* f = static_cast<nsTableRowGroupFrame*>(aFrame);
   // Don't try to use the row cursor if we have to descend into placeholders;
   // we might have rows containing placeholders, where the row's overflow
   // area doesn't intersect the dirty rect but we need to descend into the row
   // to see out of flows.
   // Note that we really want to check ShouldDescendIntoFrame for all
   // the rows in |f|, but that's exactly what we're trying to avoid, so we
   // approximate it by checking it for |f|: if it's true for any row
   // in |f| then it's true for |f| itself.
   nsIFrame* kid = aBuilder->ShouldDescendIntoFrame(f) ?
     nullptr : f->GetFirstRowContaining(aDirtyRect.y, &overflowAbove);
   if (kid) {
     // have a cursor, use it
     while (kid) {
       if (kid->GetRect().y - overflowAbove >= aDirtyRect.YMost())
         break;
       f->BuildDisplayListForChild(aBuilder, kid, aDirtyRect, aLists);
       kid = kid->GetNextSibling();
     }
     return;
   }
   // No cursor. Traverse children the hard way and build a cursor while we're at it
   nsTableRowGroupFrame::FrameCursorData* cursor = f->SetupRowCursor();
   kid = f->GetFirstPrincipalChild();
   while (kid) {
     f->BuildDisplayListForChild(aBuilder, kid, aDirtyRect, aLists);
     if (cursor) {
       if (!cursor->AppendFrame(kid)) {
         f->ClearRowCursor();
         return;
       }
     }
     kid = kid->GetNextSibling();
   }
   if (cursor) {
     cursor->FinishBuildingCursor();
   }
 }
 void
 nsTableRowGroupFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                        const nsRect&           aDirtyRect,
                                        const nsDisplayListSet& aLists)
 {
   nsDisplayTableItem* item = nullptr;
   if (IsVisibleInSelection(aBuilder)) {
     bool isRoot = aBuilder->IsAtRootOfPseudoStackingContext();
     if (isRoot) {
       // This background is created regardless of whether this frame is
       // visible or not. Visibility decisions are delegated to the
       // table background painter.
       item = new (aBuilder) nsDisplayTableRowGroupBackground(aBuilder, this);
       aLists.BorderBackground()->AppendNewToTop(item);
     }
   }
   nsTableFrame::DisplayGenericTablePart(aBuilder, this, aDirtyRect,
                                         aLists, item, DisplayRows);
 }
 int
 nsTableRowGroupFrame::GetLogicalSkipSides(const nsHTMLReflowState* aReflowState) const
 {
   int skip = 0;
   if (nullptr != GetPrevInFlow()) {
     skip |= LOGICAL_SIDE_B_START;
   }
   if (nullptr != GetNextInFlow()) {
     skip |= LOGICAL_SIDE_B_END;
   }
   return skip;
 }
 // Position and size aKidFrame and update our reflow state. The origin of
 // aKidRect is relative to the upper-left origin of our frame
 void
 nsTableRowGroupFrame::PlaceChild(nsPresContext*         aPresContext,
                                  nsRowGroupReflowState& aReflowState,
                                  nsIFrame*              aKidFrame,
                                  nsHTMLReflowMetrics&   aDesiredSize,
                                  const nsRect&          aOriginalKidRect,
                                  const nsRect&          aOriginalKidVisualOverflow)
 {
   bool isFirstReflow =
     (aKidFrame->GetStateBits() & NS_FRAME_FIRST_REFLOW) != 0;
   // Place and size the child
   FinishReflowChild(aKidFrame, aPresContext, aDesiredSize, nullptr, 0,
                     aReflowState.y, 0);
   nsTableFrame::InvalidateTableFrame(aKidFrame, aOriginalKidRect,
                                      aOriginalKidVisualOverflow, isFirstReflow);
   // Adjust the running y-offset
   aReflowState.y += aDesiredSize.Height();
   // If our height is constrained then update the available height
   if (NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height) {
     aReflowState.availSize.height -= aDesiredSize.Height();
   }
 }
 void
 nsTableRowGroupFrame::InitChildReflowState(nsPresContext&     aPresContext,
                                            bool               aBorderCollapse,
                                            nsHTMLReflowState& aReflowState)
 {
   nsMargin collapseBorder;
   nsMargin padding(0,0,0,0);
   nsMargin* pCollapseBorder = nullptr;
   if (aBorderCollapse) {
     nsTableRowFrame *rowFrame = do_QueryFrame(aReflowState.frame);
     if (rowFrame) {
       pCollapseBorder = rowFrame->GetBCBorderWidth(collapseBorder);
     }
   }
   aReflowState.Init(&aPresContext, -1, -1, pCollapseBorder, &padding);
 }
 static void
 CacheRowHeightsForPrinting(nsPresContext*   aPresContext,
                            nsTableRowFrame* aFirstRow)
 {
   for (nsTableRowFrame* row = aFirstRow; row; row = row->GetNextRow()) {
     if (!row->GetPrevInFlow()) {
       row->SetHasUnpaginatedHeight(true);
       row->SetUnpaginatedHeight(aPresContext, row->GetSize().height);
     }
   }
 }
 nsresult
 nsTableRowGroupFrame::ReflowChildren(nsPresContext*         aPresContext,
                                      nsHTMLReflowMetrics&   aDesiredSize,
                                      nsRowGroupReflowState& aReflowState,
                                      nsReflowStatus&        aStatus,
                                      bool*                aPageBreakBeforeEnd)
 {
   if (aPageBreakBeforeEnd)
     *aPageBreakBeforeEnd = false;
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   nsresult rv = NS_OK;
   const bool borderCollapse = tableFrame->IsBorderCollapse();
   nscoord cellSpacingY = tableFrame->GetCellSpacingY();
   // XXXldb Should we really be checking this rather than available height?
   // (Think about multi-column layout!)
   bool isPaginated = aPresContext->IsPaginated() &&
                        NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height;
   bool haveRow = false;
   bool reflowAllKids = aReflowState.reflowState.ShouldReflowAllKids() ||
                          tableFrame->IsGeometryDirty();
   bool needToCalcRowHeights = reflowAllKids;
   nsIFrame *prevKidFrame = nullptr;
   for (nsIFrame* kidFrame = mFrames.FirstChild(); kidFrame;
        prevKidFrame = kidFrame, kidFrame = kidFrame->GetNextSibling()) {
     nsTableRowFrame *rowFrame = do_QueryFrame(kidFrame);
     if (!rowFrame) {
       // XXXldb nsCSSFrameConstructor needs to enforce this!
       NS_NOTREACHED("yikes, a non-row child");
       continue;
     }
     haveRow = true;
     // Reflow the row frame
     if (reflowAllKids ||
         NS_SUBTREE_DIRTY(kidFrame) ||
         (aReflowState.reflowState.mFlags.mSpecialHeightReflow &&
          (isPaginated || (kidFrame->GetStateBits() &
                           NS_FRAME_CONTAINS_RELATIVE_HEIGHT)))) {
       nsRect oldKidRect = kidFrame->GetRect();
       nsRect oldKidVisualOverflow = kidFrame->GetVisualOverflowRect();
       // XXXldb We used to only pass aDesiredSize.mFlags through for the
       // incremental reflow codepath.
       nsHTMLReflowMetrics desiredSize(aReflowState.reflowState,
                                       aDesiredSize.mFlags);
       desiredSize.Width() = desiredSize.Height() = 0;
       // Reflow the child into the available space, giving it as much height as
       // it wants. We'll deal with splitting later after we've computed the row
       // heights, taking into account cells with row spans...
       nsSize kidAvailSize(aReflowState.availSize.width, NS_UNCONSTRAINEDSIZE);
       nsHTMLReflowState kidReflowState(aPresContext, aReflowState.reflowState,
                                        kidFrame, kidAvailSize,
                                        -1, -1,
                                        nsHTMLReflowState::CALLER_WILL_INIT);
       InitChildReflowState(*aPresContext, borderCollapse, kidReflowState);
       // This can indicate that columns were resized.
       if (aReflowState.reflowState.mFlags.mHResize)
         kidReflowState.mFlags.mHResize = true;
       NS_ASSERTION(kidFrame == mFrames.FirstChild() || prevKidFrame,
                    "If we're not on the first frame, we should have a "
                    "previous sibling...");
       // If prev row has nonzero YMost, then we can't be at the top of the page
       if (prevKidFrame && prevKidFrame->GetRect().YMost() > 0) {
         kidReflowState.mFlags.mIsTopOfPage = false;
       }
       rv = ReflowChild(kidFrame, aPresContext, desiredSize, kidReflowState,
 , aReflowState.y, 0, aStatus);
       // Place the child
       PlaceChild(aPresContext, aReflowState, kidFrame, desiredSize,
                  oldKidRect, oldKidVisualOverflow);
       aReflowState.y += cellSpacingY;
       if (!reflowAllKids) {
         if (IsSimpleRowFrame(aReflowState.tableFrame, kidFrame)) {
           // Inform the row of its new height.
           rowFrame->DidResize();
           // the overflow area may have changed inflate the overflow area
           const nsStylePosition *stylePos = StylePosition();
           nsStyleUnit unit = stylePos->mHeight.GetUnit();
           if (aReflowState.tableFrame->IsAutoHeight() &&
               unit != eStyleUnit_Coord) {
             // Because other cells in the row may need to be aligned
             // differently, repaint the entire row
             nsRect kidRect(0, aReflowState.y,
                            desiredSize.Width(), desiredSize.Height());
             InvalidateFrame();
           }
           else if (oldKidRect.height != desiredSize.Height())
             needToCalcRowHeights = true;
         } else {
           needToCalcRowHeights = true;
         }
       }
       if (isPaginated && aPageBreakBeforeEnd && !*aPageBreakBeforeEnd) {
         nsTableRowFrame* nextRow = rowFrame->GetNextRow();
         if (nextRow) {
           *aPageBreakBeforeEnd = nsTableFrame::PageBreakAfter(kidFrame, nextRow);
         }
       }
     } else {
       SlideChild(aReflowState, kidFrame);
       // Adjust the running y-offset so we know where the next row should be placed
       nscoord height = kidFrame->GetSize().height + cellSpacingY;
       aReflowState.y += height;
       if (NS_UNCONSTRAINEDSIZE != aReflowState.availSize.height) {
         aReflowState.availSize.height -= height;
       }
     }
     ConsiderChildOverflow(aDesiredSize.mOverflowAreas, kidFrame);
   }
   if (haveRow)
     aReflowState.y -= cellSpacingY;
   // Return our desired rect
   aDesiredSize.Width() = aReflowState.reflowState.AvailableWidth();
   aDesiredSize.Height() = aReflowState.y;
   if (aReflowState.reflowState.mFlags.mSpecialHeightReflow) {
     DidResizeRows(aDesiredSize);
     if (isPaginated) {
       CacheRowHeightsForPrinting(aPresContext, GetFirstRow());
     }
   }
   else if (needToCalcRowHeights) {
     CalculateRowHeights(aPresContext, aDesiredSize, aReflowState.reflowState);
     if (!reflowAllKids) {
       InvalidateFrame();
     }
   }
   return rv;
 }
 nsTableRowFrame*
 nsTableRowGroupFrame::GetFirstRow()
 {
   for (nsIFrame* childFrame = mFrames.FirstChild(); childFrame;
        childFrame = childFrame->GetNextSibling()) {
     nsTableRowFrame *rowFrame = do_QueryFrame(childFrame);
     if (rowFrame) {
       return rowFrame;
     }
   }
   return nullptr;
 }
 struct RowInfo {
   RowInfo() { height = pctHeight = hasStyleHeight = hasPctHeight = isSpecial = 0; }
   unsigned height;       // content height or fixed height, excluding pct height
   unsigned pctHeight:29; // pct height
   unsigned hasStyleHeight:1;
   unsigned hasPctHeight:1;
   unsigned isSpecial:1; // there is no cell originating in the row with rowspan=1 and there are at
                         // least 2 cells spanning the row and there is no style height on the row
 };
 static void
 UpdateHeights(RowInfo& aRowInfo,
               nscoord  aAdditionalHeight,
               nscoord& aTotal,
               nscoord& aUnconstrainedTotal)
 {
   aRowInfo.height += aAdditionalHeight;
   aTotal          += aAdditionalHeight;
   if (!aRowInfo.hasStyleHeight) {
     aUnconstrainedTotal += aAdditionalHeight;
   }
 }
 void
 nsTableRowGroupFrame::DidResizeRows(nsHTMLReflowMetrics& aDesiredSize)
 {
   // update the cells spanning rows with their new heights
   // this is the place where all of the cells in the row get set to the height of the row
   // Reset the overflow area
   aDesiredSize.mOverflowAreas.Clear();
   for (nsTableRowFrame* rowFrame = GetFirstRow();
        rowFrame; rowFrame = rowFrame->GetNextRow()) {
     rowFrame->DidResize();
     ConsiderChildOverflow(aDesiredSize.mOverflowAreas, rowFrame);
   }
 }
 // This calculates the height of all the rows and takes into account
 // style height on the row group, style heights on rows and cells, style heights on rowspans.
 // Actual row heights will be adjusted later if the table has a style height.
 // Even if rows don't change height, this method must be called to set the heights of each
 // cell in the row to the height of its row.
 void
 nsTableRowGroupFrame::CalculateRowHeights(nsPresContext*           aPresContext,
                                           nsHTMLReflowMetrics&     aDesiredSize,
                                           const nsHTMLReflowState& aReflowState)
 {
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   const bool isPaginated = aPresContext->IsPaginated();
   // all table cells have the same top and bottom margins, namely cellSpacingY
   nscoord cellSpacingY = tableFrame->GetCellSpacingY();
   int32_t numEffCols = tableFrame->GetEffectiveColCount();
   int32_t startRowIndex = GetStartRowIndex();
   // find the row corresponding to the row index we just found
   nsTableRowFrame* startRowFrame = GetFirstRow();
   if (!startRowFrame) return;
   // the current row group height is the y origin of the 1st row we are about to calculated a height for
   nscoord startRowGroupHeight = startRowFrame->GetPosition().y;
   int32_t numRows = GetRowCount() - (startRowFrame->GetRowIndex() - GetStartRowIndex());
   // collect the current height of each row.  nscoord* rowHeights = nullptr;
   if (numRows <= 0)
     return;
   nsTArray<RowInfo> rowInfo;
   if (!rowInfo.AppendElements(numRows)) {
     return;
   }
   bool    hasRowSpanningCell = false;
   nscoord heightOfRows = 0;
   nscoord heightOfUnStyledRows = 0;
   // Get the height of each row without considering rowspans. This will be the max of
   // the largest desired height of each cell, the largest style height of each cell,
   // the style height of the row.
   nscoord pctHeightBasis = GetHeightBasis(aReflowState);
   int32_t rowIndex; // the index in rowInfo, not among the rows in the row group
   nsTableRowFrame* rowFrame;
   for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
     nscoord nonPctHeight = rowFrame->GetContentHeight();
     if (isPaginated) {
       nonPctHeight = std::max(nonPctHeight, rowFrame->GetSize().height);
     }
     if (!rowFrame->GetPrevInFlow()) {
       if (rowFrame->HasPctHeight()) {
         rowInfo[rowIndex].hasPctHeight = true;
         rowInfo[rowIndex].pctHeight = rowFrame->GetHeight(pctHeightBasis);
       }
       rowInfo[rowIndex].hasStyleHeight = rowFrame->HasStyleHeight();
       nonPctHeight = std::max(nonPctHeight, rowFrame->GetFixedHeight());
     }
     UpdateHeights(rowInfo[rowIndex], nonPctHeight, heightOfRows, heightOfUnStyledRows);
     if (!rowInfo[rowIndex].hasStyleHeight) {
       if (isPaginated || tableFrame->HasMoreThanOneCell(rowIndex + startRowIndex)) {
         rowInfo[rowIndex].isSpecial = true;
         // iteratate the row's cell frames to see if any do not have rowspan > 1
         nsTableCellFrame* cellFrame = rowFrame->GetFirstCell();
         while (cellFrame) {
           int32_t rowSpan = tableFrame->GetEffectiveRowSpan(rowIndex + startRowIndex, *cellFrame);
           if (1 == rowSpan) {
             rowInfo[rowIndex].isSpecial = false;
             break;
           }
           cellFrame = cellFrame->GetNextCell();
         }
       }
     }
     // See if a cell spans into the row. If so we'll have to do the next step
     if (!hasRowSpanningCell) {
       if (tableFrame->RowIsSpannedInto(rowIndex + startRowIndex, numEffCols)) {
         hasRowSpanningCell = true;
       }
     }
   }
   if (hasRowSpanningCell) {
     // Get the height of cells with rowspans and allocate any extra space to the rows they span
     // iteratate the child frames and process the row frames among them
     for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
       // See if the row has an originating cell with rowspan > 1. We cannot determine this for a row in a
       // continued row group by calling RowHasSpanningCells, because the row's fif may not have any originating
       // cells yet the row may have a continued cell which originates in it.
       if (GetPrevInFlow() || tableFrame->RowHasSpanningCells(startRowIndex + rowIndex, numEffCols)) {
         nsTableCellFrame* cellFrame = rowFrame->GetFirstCell();
         // iteratate the row's cell frames
         while (cellFrame) {
           int32_t rowSpan = tableFrame->GetEffectiveRowSpan(rowIndex + startRowIndex, *cellFrame);
           if ((rowIndex + rowSpan) > numRows) {
             // there might be rows pushed already to the nextInFlow
             rowSpan = numRows - rowIndex;
           }
           if (rowSpan > 1) { // a cell with rowspan > 1, determine the height of the rows it spans
             nscoord heightOfRowsSpanned = 0;
             nscoord heightOfUnStyledRowsSpanned = 0;
             nscoord numSpecialRowsSpanned = 0;
             nscoord cellSpacingTotal = 0;
             int32_t spanX;
             for (spanX = 0; spanX < rowSpan; spanX++) {
               heightOfRowsSpanned += rowInfo[rowIndex + spanX].height;
               if (!rowInfo[rowIndex + spanX].hasStyleHeight) {
                 heightOfUnStyledRowsSpanned += rowInfo[rowIndex + spanX].height;
               }
               if (0 != spanX) {
                 cellSpacingTotal += cellSpacingY;
               }
               if (rowInfo[rowIndex + spanX].isSpecial) {
                 numSpecialRowsSpanned++;
               }
             }
             nscoord heightOfAreaSpanned = heightOfRowsSpanned + cellSpacingTotal;
             // get the height of the cell
             nsSize cellFrameSize = cellFrame->GetSize();
             nsSize cellDesSize = cellFrame->GetDesiredSize();
             rowFrame->CalculateCellActualHeight(cellFrame, cellDesSize.height);
             cellFrameSize.height = cellDesSize.height;
             if (cellFrame->HasVerticalAlignBaseline()) {
               // to ensure that a spanning cell with a long descender doesn't
               // collide with the next row, we need to take into account the shift
               // that will be done to align the cell on the baseline of the row.
               cellFrameSize.height += rowFrame->GetMaxCellAscent() -
                                       cellFrame->GetCellBaseline();
             }
             if (heightOfAreaSpanned < cellFrameSize.height) {
               // the cell's height is larger than the available space of the rows it
               // spans so distribute the excess height to the rows affected
               nscoord extra     = cellFrameSize.height - heightOfAreaSpanned;
               nscoord extraUsed = 0;
               if (0 == numSpecialRowsSpanned) {
                 //NS_ASSERTION(heightOfRowsSpanned > 0, "invalid row span situation");
                 bool haveUnStyledRowsSpanned = (heightOfUnStyledRowsSpanned > 0);
                 nscoord divisor = (haveUnStyledRowsSpanned)
                                   ? heightOfUnStyledRowsSpanned : heightOfRowsSpanned;
                 if (divisor > 0) {
                   for (spanX = rowSpan - 1; spanX >= 0; spanX--) {
                     if (!haveUnStyledRowsSpanned || !rowInfo[rowIndex + spanX].hasStyleHeight) {
                       // The amount of additional space each row gets is proportional to its height
                       float percent = ((float)rowInfo[rowIndex + spanX].height) / ((float)divisor);
                       // give rows their percentage, except for the first row which gets the remainder
                       nscoord extraForRow = (0 == spanX) ? extra - extraUsed
                                                          : NSToCoordRound(((float)(extra)) * percent);
                       extraForRow = std::min(extraForRow, extra - extraUsed);
                       // update the row height
                       UpdateHeights(rowInfo[rowIndex + spanX], extraForRow, heightOfRows, heightOfUnStyledRows);
                       extraUsed += extraForRow;
                       if (extraUsed >= extra) {
                         NS_ASSERTION((extraUsed == extra), "invalid row height calculation");
                         break;
                       }
                     }
                   }
                 }
                 else {
                   // put everything in the last row
                   UpdateHeights(rowInfo[rowIndex + rowSpan - 1], extra, heightOfRows, heightOfUnStyledRows);
                 }
               }
               else {
                 // give the extra to the special rows
                 nscoord numSpecialRowsAllocated = 0;
                 for (spanX = rowSpan - 1; spanX >= 0; spanX--) {
                   if (rowInfo[rowIndex + spanX].isSpecial) {
                     // The amount of additional space each degenerate row gets is proportional to the number of them
                     float percent = 1.0f / ((float)numSpecialRowsSpanned);
                     // give rows their percentage, except for the first row which gets the remainder
                     nscoord extraForRow = (numSpecialRowsSpanned - 1 == numSpecialRowsAllocated)
                                           ? extra - extraUsed
                                           : NSToCoordRound(((float)(extra)) * percent);
                     extraForRow = std::min(extraForRow, extra - extraUsed);
                     // update the row height
                     UpdateHeights(rowInfo[rowIndex + spanX], extraForRow, heightOfRows, heightOfUnStyledRows);
                     extraUsed += extraForRow;
                     if (extraUsed >= extra) {
                       NS_ASSERTION((extraUsed == extra), "invalid row height calculation");
                       break;
                     }
                   }
                 }
               }
             }
           } // if (rowSpan > 1)
           cellFrame = cellFrame->GetNextCell();
         } // while (cellFrame)
       } // if (tableFrame->RowHasSpanningCells(startRowIndex + rowIndex) {
     } // while (rowFrame)
   }
   // pct height rows have already got their content heights. Give them their pct heights up to pctHeightBasis
   nscoord extra = pctHeightBasis - heightOfRows;
   for (rowFrame = startRowFrame, rowIndex = 0; rowFrame && (extra > 0); rowFrame = rowFrame->GetNextRow(), rowIndex++) {
     RowInfo& rInfo = rowInfo[rowIndex];
     if (rInfo.hasPctHeight) {
       nscoord rowExtra = (rInfo.pctHeight > rInfo.height)
                          ? rInfo.pctHeight - rInfo.height: 0;
       rowExtra = std::min(rowExtra, extra);
       UpdateHeights(rInfo, rowExtra, heightOfRows, heightOfUnStyledRows);
       extra -= rowExtra;
     }
   }
   bool styleHeightAllocation = false;
   nscoord rowGroupHeight = startRowGroupHeight + heightOfRows + ((numRows - 1) * cellSpacingY);
   // if we have a style height, allocate the extra height to unconstrained rows
   if ((aReflowState.ComputedHeight() > rowGroupHeight) &&
       (NS_UNCONSTRAINEDSIZE != aReflowState.ComputedHeight())) {
     nscoord extraComputedHeight = aReflowState.ComputedHeight() - rowGroupHeight;
     nscoord extraUsed = 0;
     bool haveUnStyledRows = (heightOfUnStyledRows > 0);
     nscoord divisor = (haveUnStyledRows)
                       ? heightOfUnStyledRows : heightOfRows;
     if (divisor > 0) {
       styleHeightAllocation = true;
       for (rowIndex = 0; rowIndex < numRows; rowIndex++) {
         if (!haveUnStyledRows || !rowInfo[rowIndex].hasStyleHeight) {
           // The amount of additional space each row gets is based on the
           // percentage of space it occupies
           float percent = ((float)rowInfo[rowIndex].height) / ((float)divisor);
           // give rows their percentage, except for the last row which gets the remainder
           nscoord extraForRow = (numRows - 1 == rowIndex)
                                 ? extraComputedHeight - extraUsed
                                 : NSToCoordRound(((float)extraComputedHeight) * percent);
           extraForRow = std::min(extraForRow, extraComputedHeight - extraUsed);
           // update the row height
           UpdateHeights(rowInfo[rowIndex], extraForRow, heightOfRows, heightOfUnStyledRows);
           extraUsed += extraForRow;
           if (extraUsed >= extraComputedHeight) {
             NS_ASSERTION((extraUsed == extraComputedHeight), "invalid row height calculation");
             break;
           }
         }
       }
     }
     rowGroupHeight = aReflowState.ComputedHeight();
   }
   nscoord yOrigin = startRowGroupHeight;
   // update the rows with their (potentially) new heights
   for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
     nsRect rowBounds = rowFrame->GetRect();
     nsRect rowVisualOverflow = rowFrame->GetVisualOverflowRect();
     bool movedFrame = (rowBounds.y != yOrigin);
     nscoord rowHeight = (rowInfo[rowIndex].height > 0) ? rowInfo[rowIndex].height : 0;
     if (movedFrame || (rowHeight != rowBounds.height)) {
       // Resize/move the row to its final size and position
       if (movedFrame) {
         rowFrame->InvalidateFrameSubtree();
       }
       rowFrame->SetRect(nsRect(rowBounds.x, yOrigin, rowBounds.width,
                                rowHeight));
       nsTableFrame::InvalidateTableFrame(rowFrame, rowBounds, rowVisualOverflow,
                                          false);
     }
     if (movedFrame) {
       nsTableFrame::RePositionViews(rowFrame);
       // XXXbz we don't need to update our overflow area?
     }
     yOrigin += rowHeight + cellSpacingY;
   }
   if (isPaginated && styleHeightAllocation) {
     // since the row group has a style height, cache the row heights, so next in flows can honor them
     CacheRowHeightsForPrinting(aPresContext, GetFirstRow());
   }
   DidResizeRows(aDesiredSize);
   aDesiredSize.Height() = rowGroupHeight; // Adjust our desired size
 }
 nscoord
 nsTableRowGroupFrame::CollapseRowGroupIfNecessary(nscoord aYTotalOffset,
                                                   nscoord aWidth)
 {
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   const nsStyleVisibility* groupVis = StyleVisibility();
   bool collapseGroup = (NS_STYLE_VISIBILITY_COLLAPSE == groupVis->mVisible);
   if (collapseGroup) {
     tableFrame->SetNeedToCollapse(true);
   }
   nsOverflowAreas overflow;
   nsTableRowFrame* rowFrame= GetFirstRow();
   bool didCollapse = false;
   nscoord yGroupOffset = 0;
   while (rowFrame) {
     yGroupOffset += rowFrame->CollapseRowIfNecessary(yGroupOffset,
                                                      aWidth, collapseGroup,
                                                      didCollapse);
     ConsiderChildOverflow(overflow, rowFrame);
     rowFrame = rowFrame->GetNextRow();
   }
   nsRect groupRect = GetRect();
   nsRect oldGroupRect = groupRect;
   nsRect oldGroupVisualOverflow = GetVisualOverflowRect();
   groupRect.height -= yGroupOffset;
   if (didCollapse) {
     // add back the cellspacing between rowgroups
     groupRect.height += tableFrame->GetCellSpacingY();
   }
   groupRect.y -= aYTotalOffset;
   groupRect.width = aWidth;
   if (aYTotalOffset != 0) {
     InvalidateFrameSubtree();
   }
   SetRect(groupRect);
   overflow.UnionAllWith(nsRect(0, 0, groupRect.width, groupRect.height));
   FinishAndStoreOverflow(overflow, groupRect.Size());
   nsTableFrame::RePositionViews(this);
   nsTableFrame::InvalidateTableFrame(this, oldGroupRect, oldGroupVisualOverflow,
                                      false);
   return yGroupOffset;
 }
 // Move a child that was skipped during a reflow.
 void
 nsTableRowGroupFrame::SlideChild(nsRowGroupReflowState& aReflowState,
                                  nsIFrame*              aKidFrame)
 {
   // Move the frame if we need to
   nsPoint oldPosition = aKidFrame->GetPosition();
   nsPoint newPosition = oldPosition;
   newPosition.y = aReflowState.y;
   if (oldPosition.y != newPosition.y) {
     aKidFrame->InvalidateFrameSubtree();
     aKidFrame->SetPosition(newPosition);
     nsTableFrame::RePositionViews(aKidFrame);
     aKidFrame->InvalidateFrameSubtree();
   }
 }
 // Create a continuing frame, add it to the child list, and then push it
 // and the frames that follow
 void
 nsTableRowGroupFrame::CreateContinuingRowFrame(nsPresContext& aPresContext,
                                                nsIFrame&      aRowFrame,
                                                nsIFrame**     aContRowFrame)
 {
   // XXX what is the row index?
   if (!aContRowFrame) {NS_ASSERTION(false, "bad call"); return;}
   // create the continuing frame which will create continuing cell frames
   *aContRowFrame = aPresContext.PresShell()->FrameConstructor()->
     CreateContinuingFrame(&aPresContext, &aRowFrame, this);
   // Add the continuing row frame to the child list
   mFrames.InsertFrame(nullptr, &aRowFrame, *aContRowFrame);
   // Push the continuing row frame and the frames that follow
   PushChildren(*aContRowFrame, &aRowFrame);
 }
 // Reflow the cells with rowspan > 1 which originate between aFirstRow
 // and end on or after aLastRow. aFirstTruncatedRow is the highest row on the
 // page that contains a cell which cannot split on this page
 void
 nsTableRowGroupFrame::SplitSpanningCells(nsPresContext&           aPresContext,
                                          const nsHTMLReflowState& aReflowState,
                                          nsTableFrame&            aTable,
                                          nsTableRowFrame&         aFirstRow,
                                          nsTableRowFrame&         aLastRow,
                                          bool                     aFirstRowIsTopOfPage,
                                          nscoord                  aSpanningRowBottom,
                                          nsTableRowFrame*&        aContRow,
                                          nsTableRowFrame*&        aFirstTruncatedRow,
                                          nscoord&                 aDesiredHeight)
 {
   NS_ASSERTION(aSpanningRowBottom >= 0, "Can't split negative heights");
   aFirstTruncatedRow = nullptr;
   aDesiredHeight     = 0;
   const bool borderCollapse = aTable.IsBorderCollapse();
   int32_t lastRowIndex = aLastRow.GetRowIndex();
   bool wasLast = false;
   bool haveRowSpan = false;
   // Iterate the rows between aFirstRow and aLastRow
   for (nsTableRowFrame* row = &aFirstRow; !wasLast; row = row->GetNextRow()) {
     wasLast = (row == &aLastRow);
     int32_t rowIndex = row->GetRowIndex();
     nsPoint rowPos = row->GetPosition();
     // Iterate the cells looking for those that have rowspan > 1
     for (nsTableCellFrame* cell = row->GetFirstCell(); cell; cell = cell->GetNextCell()) {
       int32_t rowSpan = aTable.GetEffectiveRowSpan(rowIndex, *cell);
       // Only reflow rowspan > 1 cells which span aLastRow. Those which don't span aLastRow
       // were reflowed correctly during the unconstrained height reflow.
       if ((rowSpan > 1) && (rowIndex + rowSpan > lastRowIndex)) {
         haveRowSpan = true;
         nsReflowStatus status;
         // Ask the row to reflow the cell to the height of all the rows it spans up through aLastRow
         // aAvailHeight is the space between the row group start and the end of the page
         nscoord cellAvailHeight = aSpanningRowBottom - rowPos.y;
         NS_ASSERTION(cellAvailHeight >= 0, "No space for cell?");
         bool isTopOfPage = (row == &aFirstRow) && aFirstRowIsTopOfPage;
         nsRect rowRect = row->GetRect();
         nsSize rowAvailSize(aReflowState.AvailableWidth(),
                             std::max(aReflowState.AvailableHeight() - rowRect.y,
 ));
         // don't let the available height exceed what
         // CalculateRowHeights set for it
         rowAvailSize.height = std::min(rowAvailSize.height, rowRect.height);
         nsHTMLReflowState rowReflowState(&aPresContext, aReflowState,
                                          row, rowAvailSize,
                                          -1, -1,
                                          nsHTMLReflowState::CALLER_WILL_INIT);
         InitChildReflowState(aPresContext, borderCollapse, rowReflowState);
         rowReflowState.mFlags.mIsTopOfPage = isTopOfPage; // set top of page
         nscoord cellHeight = row->ReflowCellFrame(&aPresContext, rowReflowState,
                                                   isTopOfPage, cell,
                                                   cellAvailHeight, status);
         aDesiredHeight = std::max(aDesiredHeight, rowPos.y + cellHeight);
         if (NS_FRAME_IS_COMPLETE(status)) {
           if (cellHeight > cellAvailHeight) {
             aFirstTruncatedRow = row;
             if ((row != &aFirstRow) || !aFirstRowIsTopOfPage) {
               // return now, since we will be getting another reflow after either (1) row is
               // moved to the next page or (2) the row group is moved to the next page
               return;
             }
           }
         }
         else {
           if (!aContRow) {
             CreateContinuingRowFrame(aPresContext, aLastRow, (nsIFrame**)&aContRow);
           }
           if (aContRow) {
             if (row != &aLastRow) {
               // aContRow needs a continuation for cell, since cell spanned into aLastRow
               // but does not originate there
               nsTableCellFrame* contCell = static_cast<nsTableCellFrame*>(
                 aPresContext.PresShell()->FrameConstructor()->
                   CreateContinuingFrame(&aPresContext, cell, &aLastRow));
               int32_t colIndex;
               cell->GetColIndex(colIndex);
               aContRow->InsertCellFrame(contCell, colIndex);
             }
           }
         }
       }
     }
   }
   if (!haveRowSpan) {
     aDesiredHeight = aLastRow.GetRect().YMost();
   }
 }
 // Remove the next-in-flow of the row, its cells and their cell blocks. This
 // is necessary in case the row doesn't need a continuation later on or needs
 // a continuation which doesn't have the same number of cells that now exist.
 void
 nsTableRowGroupFrame::UndoContinuedRow(nsPresContext*   aPresContext,
                                        nsTableRowFrame* aRow)
 {
   if (!aRow) return; // allow null aRow to avoid callers doing null checks
   // rowBefore was the prev-sibling of aRow's next-sibling before aRow was created
   nsTableRowFrame* rowBefore = (nsTableRowFrame*)aRow->GetPrevInFlow();
   NS_PRECONDITION(mFrames.ContainsFrame(rowBefore),
                   "rowBefore not in our frame list?");
   AutoFrameListPtr overflows(aPresContext, StealOverflowFrames());
   if (!rowBefore || !overflows || overflows->IsEmpty() ||
       overflows->FirstChild() != aRow) {
     NS_ERROR("invalid continued row");
     return;
   }
   // Destroy aRow, its cells, and their cell blocks. Cell blocks that have split
   // will not have reflowed yet to pick up content from any overflow lines.
   overflows->DestroyFrame(aRow);
   // Put the overflow rows into our child list
   if (!overflows->IsEmpty()) {
     mFrames.InsertFrames(nullptr, rowBefore, *overflows);
   }
 }
 static nsTableRowFrame*
 GetRowBefore(nsTableRowFrame& aStartRow,
              nsTableRowFrame& aRow)
 {
   nsTableRowFrame* rowBefore = nullptr;
   for (nsTableRowFrame* sib = &aStartRow; sib && (sib != &aRow); sib = sib->GetNextRow()) {
     rowBefore = sib;
   }
   return rowBefore;
 }
 nsresult
 nsTableRowGroupFrame::SplitRowGroup(nsPresContext*           aPresContext,
                                     nsHTMLReflowMetrics&     aDesiredSize,
                                     const nsHTMLReflowState& aReflowState,
                                     nsTableFrame*            aTableFrame,
                                     nsReflowStatus&          aStatus,
                                     bool                     aRowForcedPageBreak)
 {
   NS_PRECONDITION(aPresContext->IsPaginated(), "SplitRowGroup currently supports only paged media");
   nsresult rv = NS_OK;
   nsTableRowFrame* prevRowFrame = nullptr;
   aDesiredSize.Height() = 0;
   nscoord availWidth  = aReflowState.AvailableWidth();
   nscoord availHeight = aReflowState.AvailableHeight();
   const bool borderCollapse = aTableFrame->IsBorderCollapse();
   nscoord cellSpacingY = aTableFrame->GetCellSpacingY();
   // get the page height
   nscoord pageHeight = aPresContext->GetPageSize().height;
   NS_ASSERTION(pageHeight != NS_UNCONSTRAINEDSIZE,
                "The table shouldn't be split when there should be space");
   bool isTopOfPage = aReflowState.mFlags.mIsTopOfPage;
   nsTableRowFrame* firstRowThisPage = GetFirstRow();
   // Need to dirty the table's geometry, or else the row might skip
   // reflowing its cell as an optimization.
   aTableFrame->SetGeometryDirty();
   // Walk each of the row frames looking for the first row frame that doesn't fit
   // in the available space
   for (nsTableRowFrame* rowFrame = firstRowThisPage; rowFrame; rowFrame = rowFrame->GetNextRow()) {
     bool rowIsOnPage = true;
     nsRect rowRect = rowFrame->GetRect();
     // See if the row fits on this page
     if (rowRect.YMost() > availHeight) {
       nsTableRowFrame* contRow = nullptr;
       // Reflow the row in the availabe space and have it split if it is the 1st
       // row (on the page) or there is at least 5% of the current page available
       // XXX this 5% should be made a preference
       if (!prevRowFrame || (availHeight - aDesiredSize.Height() > pageHeight / 20)) {
         nsSize availSize(availWidth, std::max(availHeight - rowRect.y, 0));
         // don't let the available height exceed what CalculateRowHeights set for it
         availSize.height = std::min(availSize.height, rowRect.height);
         nsHTMLReflowState rowReflowState(aPresContext, aReflowState,
                                          rowFrame, availSize,
                                          -1, -1,
                                          nsHTMLReflowState::CALLER_WILL_INIT);
         InitChildReflowState(*aPresContext, borderCollapse, rowReflowState);
         rowReflowState.mFlags.mIsTopOfPage = isTopOfPage; // set top of page
         nsHTMLReflowMetrics rowMetrics(aReflowState);
         // Get the old size before we reflow.
         nsRect oldRowRect = rowFrame->GetRect();
         nsRect oldRowVisualOverflow = rowFrame->GetVisualOverflowRect();
         // Reflow the cell with the constrained height. A cell with rowspan >1 will get this
         // reflow later during SplitSpanningCells.
         rv = ReflowChild(rowFrame, aPresContext, rowMetrics, rowReflowState,
 , 0, NS_FRAME_NO_MOVE_FRAME, aStatus);
         if (NS_FAILED(rv)) return rv;
         rowFrame->SetSize(nsSize(rowMetrics.Width(), rowMetrics.Height()));
         rowFrame->DidReflow(aPresContext, nullptr, nsDidReflowStatus::FINISHED);
         rowFrame->DidResize();
         if (!aRowForcedPageBreak && !NS_FRAME_IS_FULLY_COMPLETE(aStatus) &&
             ShouldAvoidBreakInside(aReflowState)) {
           aStatus = NS_INLINE_LINE_BREAK_BEFORE();
           break;
         }
         nsTableFrame::InvalidateTableFrame(rowFrame, oldRowRect,
                                            oldRowVisualOverflow,
                                            false);
         if (NS_FRAME_IS_NOT_COMPLETE(aStatus)) {
           // The row frame is incomplete and all of the rowspan 1 cells' block frames split
           if ((rowMetrics.Height() <= rowReflowState.AvailableHeight()) || isTopOfPage) {
             // The row stays on this page because either it split ok or we're on the top of page.
             // If top of page and the height exceeded the avail height, then there will be data loss
             NS_ASSERTION(rowMetrics.Height() <= rowReflowState.AvailableHeight(),
                          "data loss - incomplete row needed more height than available, on top of page");
             CreateContinuingRowFrame(*aPresContext, *rowFrame, (nsIFrame**)&contRow);
             if (contRow) {
               aDesiredSize.Height() += rowMetrics.Height();
               if (prevRowFrame)
                 aDesiredSize.Height() += cellSpacingY;
             }
             else return NS_ERROR_NULL_POINTER;
           }
           else {
             // Put the row on the next page to give it more height
             rowIsOnPage = false;
           }
         }
         else {
           // The row frame is complete because either (1) its minimum height is greater than the
           // available height we gave it, or (2) it may have been given a larger height through
           // style than its content, or (3) it contains a rowspan >1 cell which hasn't been
           // reflowed with a constrained height yet (we will find out when SplitSpanningCells is
           // called below)
           if (rowMetrics.Height() > availSize.height ||
               (NS_INLINE_IS_BREAK_BEFORE(aStatus) && !aRowForcedPageBreak)) {
             // cases (1) and (2)
             if (isTopOfPage) {
               // We're on top of the page, so keep the row on this page. There will be data loss.
               // Push the row frame that follows
               nsTableRowFrame* nextRowFrame = rowFrame->GetNextRow();
               if (nextRowFrame) {
                 aStatus = NS_FRAME_NOT_COMPLETE;
               }
               aDesiredSize.Height() += rowMetrics.Height();
               if (prevRowFrame)
                 aDesiredSize.Height() += cellSpacingY;
               NS_WARNING("data loss - complete row needed more height than available, on top of page");
             }
             else {
               // We're not on top of the page, so put the row on the next page to give it more height
               rowIsOnPage = false;
             }
           }
         }
       } //if (!prevRowFrame || (availHeight - aDesiredSize.Height() > pageHeight / 20))
       else {
         // put the row on the next page to give it more height
         rowIsOnPage = false;
       }
       nsTableRowFrame* lastRowThisPage = rowFrame;
       nscoord spanningRowBottom = availHeight;
       if (!rowIsOnPage) {
         NS_ASSERTION(!contRow, "We should not have created a continuation if none of this row fits");
         if (!aRowForcedPageBreak && ShouldAvoidBreakInside(aReflowState)) {
           aStatus = NS_INLINE_LINE_BREAK_BEFORE();
           break;
         }
         if (prevRowFrame) {
           spanningRowBottom = prevRowFrame->GetRect().YMost();
           lastRowThisPage = prevRowFrame;
           isTopOfPage = (lastRowThisPage == firstRowThisPage) && aReflowState.mFlags.mIsTopOfPage;
           aStatus = NS_FRAME_NOT_COMPLETE;
         }
         else {
           // We can't push children, so let our parent reflow us again with more space
           aDesiredSize.Height() = rowRect.YMost();
           aStatus = NS_FRAME_COMPLETE;
           break;
         }
       }
       // reflow the cells with rowspan >1 that occur on the page
       nsTableRowFrame* firstTruncatedRow;
       nscoord yMost;
       SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame, *firstRowThisPage,
                          *lastRowThisPage, aReflowState.mFlags.mIsTopOfPage, spanningRowBottom, contRow,
                          firstTruncatedRow, yMost);
       if (firstTruncatedRow) {
         // A rowspan >1 cell did not fit (and could not split) in the space we gave it
         if (firstTruncatedRow == firstRowThisPage) {
           if (aReflowState.mFlags.mIsTopOfPage) {
             NS_WARNING("data loss in a row spanned cell");
           }
           else {
             // We can't push children, so let our parent reflow us again with more space
             aDesiredSize.Height() = rowRect.YMost();
             aStatus = NS_FRAME_COMPLETE;
             UndoContinuedRow(aPresContext, contRow);
             contRow = nullptr;
           }
         }
         else { // (firstTruncatedRow != firstRowThisPage)
           // Try to put firstTruncateRow on the next page
           nsTableRowFrame* rowBefore = ::GetRowBefore(*firstRowThisPage, *firstTruncatedRow);
           nscoord oldSpanningRowBottom = spanningRowBottom;
           spanningRowBottom = rowBefore->GetRect().YMost();
           UndoContinuedRow(aPresContext, contRow);
           contRow = nullptr;
           nsTableRowFrame* oldLastRowThisPage = lastRowThisPage;
           lastRowThisPage = rowBefore;
           aStatus = NS_FRAME_NOT_COMPLETE;
           // Call SplitSpanningCells again with rowBefore as the last row on the page
           SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame,
                              *firstRowThisPage, *rowBefore, aReflowState.mFlags.mIsTopOfPage,
                              spanningRowBottom, contRow, firstTruncatedRow, aDesiredSize.Height());
           if (firstTruncatedRow) {
             if (aReflowState.mFlags.mIsTopOfPage) {
               // We were better off with the 1st call to SplitSpanningCells, do it again
               UndoContinuedRow(aPresContext, contRow);
               contRow = nullptr;
               lastRowThisPage = oldLastRowThisPage;
               spanningRowBottom = oldSpanningRowBottom;
               SplitSpanningCells(*aPresContext, aReflowState, *aTableFrame, *firstRowThisPage,
                                  *lastRowThisPage, aReflowState.mFlags.mIsTopOfPage, spanningRowBottom, contRow,
                                  firstTruncatedRow, aDesiredSize.Height());
               NS_WARNING("data loss in a row spanned cell");
             }
             else {
               // Let our parent reflow us again with more space
               aDesiredSize.Height() = rowRect.YMost();
               aStatus = NS_FRAME_COMPLETE;
               UndoContinuedRow(aPresContext, contRow);
               contRow = nullptr;
             }
           }
         } // if (firstTruncatedRow == firstRowThisPage)
       } // if (firstTruncatedRow)
       else {
         aDesiredSize.Height() = std::max(aDesiredSize.Height(), yMost);
         if (contRow) {
           aStatus = NS_FRAME_NOT_COMPLETE;
         }
       }
       if (NS_FRAME_IS_NOT_COMPLETE(aStatus) && !contRow) {
         nsTableRowFrame* nextRow = lastRowThisPage->GetNextRow();
         if (nextRow) {
           PushChildren(nextRow, lastRowThisPage);
         }
       }
       break;
     } // if (rowRect.YMost() > availHeight)
     else {
       aDesiredSize.Height() = rowRect.YMost();
       prevRowFrame = rowFrame;
       // see if there is a page break after the row
       nsTableRowFrame* nextRow = rowFrame->GetNextRow();
       if (nextRow && nsTableFrame::PageBreakAfter(rowFrame, nextRow)) {
         PushChildren(nextRow, rowFrame);
         aStatus = NS_FRAME_NOT_COMPLETE;
         break;
       }
     }
     // after the 1st row that has a height, we can't be on top
     // of the page anymore.
     isTopOfPage = isTopOfPage && rowRect.YMost() == 0;
   }
   return NS_OK;
 }
 /** Layout the entire row group.
   * This method stacks rows vertically according to HTML 4.0 rules.
   * Rows are responsible for layout of their children.
   */
 nsresult
 nsTableRowGroupFrame::Reflow(nsPresContext*           aPresContext,
                              nsHTMLReflowMetrics&     aDesiredSize,
                              const nsHTMLReflowState& aReflowState,
                              nsReflowStatus&          aStatus)
 {
   DO_GLOBAL_REFLOW_COUNT("nsTableRowGroupFrame");
   DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
   nsresult rv = NS_OK;
   aStatus     = NS_FRAME_COMPLETE;
   // Row geometry may be going to change so we need to invalidate any row cursor.
   ClearRowCursor();
   // see if a special height reflow needs to occur due to having a pct height
   nsTableFrame::CheckRequestSpecialHeightReflow(aReflowState);
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   nsRowGroupReflowState state(aReflowState, tableFrame);
   const nsStyleVisibility* groupVis = StyleVisibility();
   bool collapseGroup = (NS_STYLE_VISIBILITY_COLLAPSE == groupVis->mVisible);
   if (collapseGroup) {
     tableFrame->SetNeedToCollapse(true);
   }
   // Check for an overflow list
   MoveOverflowToChildList();
   // Reflow the existing frames.
   bool splitDueToPageBreak = false;
   rv = ReflowChildren(aPresContext, aDesiredSize, state, aStatus,
                       &splitDueToPageBreak);
   // See if all the frames fit. Do not try to split anything if we're
   // not paginated ... we can't split across columns yet.
   if (aReflowState.mFlags.mTableIsSplittable &&
       NS_UNCONSTRAINEDSIZE != aReflowState.AvailableHeight() &&
       (NS_FRAME_NOT_COMPLETE == aStatus || splitDueToPageBreak ||
        aDesiredSize.Height() > aReflowState.AvailableHeight())) {
     // Nope, find a place to split the row group
     bool specialReflow = (bool)aReflowState.mFlags.mSpecialHeightReflow;
     ((nsHTMLReflowState::ReflowStateFlags&)aReflowState.mFlags).mSpecialHeightReflow = false;
     SplitRowGroup(aPresContext, aDesiredSize, aReflowState, tableFrame, aStatus,
                   splitDueToPageBreak);
     ((nsHTMLReflowState::ReflowStateFlags&)aReflowState.mFlags).mSpecialHeightReflow = specialReflow;
   }
   // XXXmats The following is just bogus.  We leave it here for now because
   // ReflowChildren should pull up rows from our next-in-flow before returning
   // a Complete status, but doesn't (bug 804888).
   if (GetNextInFlow() && GetNextInFlow()->GetFirstPrincipalChild()) {
     NS_FRAME_SET_INCOMPLETE(aStatus);
   }
   SetHasStyleHeight((NS_UNCONSTRAINEDSIZE != aReflowState.ComputedHeight()) &&
                     (aReflowState.ComputedHeight() > 0));
   // just set our width to what was available. The table will calculate the width and not use our value.
   aDesiredSize.Width() = aReflowState.AvailableWidth();
   aDesiredSize.UnionOverflowAreasWithDesiredBounds();
   // If our parent is in initial reflow, it'll handle invalidating our
   // entire overflow rect.
   if (!(GetParent()->GetStateBits() & NS_FRAME_FIRST_REFLOW) &&
       nsSize(aDesiredSize.Width(), aDesiredSize.Height()) != mRect.Size()) {
     InvalidateFrame();
   }
   FinishAndStoreOverflow(&aDesiredSize);
   NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
   return rv;
 }
 bool
 nsTableRowGroupFrame::UpdateOverflow()
 {
   // Row cursor invariants depend on the visual overflow area of the rows,
   // which may have changed, so we need to clear the cursor now.
   ClearRowCursor();
   return nsContainerFrame::UpdateOverflow();
 }
 /* virtual */ void
 nsTableRowGroupFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
 {
   nsContainerFrame::DidSetStyleContext(aOldStyleContext);
   if (!aOldStyleContext) //avoid this on init
     return;
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   if (tableFrame->IsBorderCollapse() &&
       tableFrame->BCRecalcNeeded(aOldStyleContext, StyleContext())) {
     nsIntRect damageArea(0, GetStartRowIndex(), tableFrame->GetColCount(),
                          GetRowCount());
     tableFrame->AddBCDamageArea(damageArea);
   }
 }
 nsresult
 nsTableRowGroupFrame::AppendFrames(ChildListID     aListID,
                                    nsFrameList&    aFrameList)
 {
   NS_ASSERTION(aListID == kPrincipalList, "unexpected child list");
   ClearRowCursor();
   // collect the new row frames in an array
   // XXXbz why are we doing the QI stuff?  There shouldn't be any non-rows here.
   nsAutoTArray<nsTableRowFrame*, 8> rows;
   for (nsFrameList::Enumerator e(aFrameList); !e.AtEnd(); e.Next()) {
     nsTableRowFrame *rowFrame = do_QueryFrame(e.get());
     NS_ASSERTION(rowFrame, "Unexpected frame; frame constructor screwed up");
     if (rowFrame) {
       NS_ASSERTION(NS_STYLE_DISPLAY_TABLE_ROW ==
                      e.get()->StyleDisplay()->mDisplay,
                    "wrong display type on rowframe");
       rows.AppendElement(rowFrame);
     }
   }
   int32_t rowIndex = GetRowCount();
   // Append the frames to the sibling chain
   mFrames.AppendFrames(nullptr, aFrameList);
   if (rows.Length() > 0) {
     nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
     tableFrame->AppendRows(this, rowIndex, rows);
     PresContext()->PresShell()->
       FrameNeedsReflow(this, nsIPresShell::eTreeChange,
                        NS_FRAME_HAS_DIRTY_CHILDREN);
     tableFrame->SetGeometryDirty();
   }
   return NS_OK;
 }
 nsresult
 nsTableRowGroupFrame::InsertFrames(ChildListID     aListID,
                                    nsIFrame*       aPrevFrame,
                                    nsFrameList&    aFrameList)
 {
   NS_ASSERTION(aListID == kPrincipalList, "unexpected child list");
   NS_ASSERTION(!aPrevFrame || aPrevFrame->GetParent() == this,
                "inserting after sibling frame with different parent");
   ClearRowCursor();
   // collect the new row frames in an array
   // XXXbz why are we doing the QI stuff?  There shouldn't be any non-rows here.
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   nsTArray<nsTableRowFrame*> rows;
   bool gotFirstRow = false;
   for (nsFrameList::Enumerator e(aFrameList); !e.AtEnd(); e.Next()) {
     nsTableRowFrame *rowFrame = do_QueryFrame(e.get());
     NS_ASSERTION(rowFrame, "Unexpected frame; frame constructor screwed up");
     if (rowFrame) {
       NS_ASSERTION(NS_STYLE_DISPLAY_TABLE_ROW ==
                      e.get()->StyleDisplay()->mDisplay,
                    "wrong display type on rowframe");
       rows.AppendElement(rowFrame);
       if (!gotFirstRow) {
         rowFrame->SetFirstInserted(true);
         gotFirstRow = true;
         tableFrame->SetRowInserted(true);
       }
     }
   }
   int32_t startRowIndex = GetStartRowIndex();
   // Insert the frames in the sibling chain
   mFrames.InsertFrames(nullptr, aPrevFrame, aFrameList);
   int32_t numRows = rows.Length();
   if (numRows > 0) {
     nsTableRowFrame* prevRow = (nsTableRowFrame *)nsTableFrame::GetFrameAtOrBefore(this, aPrevFrame, nsGkAtoms::tableRowFrame);
     int32_t rowIndex = (prevRow) ? prevRow->GetRowIndex() + 1 : startRowIndex;
     tableFrame->InsertRows(this, rows, rowIndex, true);
     PresContext()->PresShell()->
       FrameNeedsReflow(this, nsIPresShell::eTreeChange,
                        NS_FRAME_HAS_DIRTY_CHILDREN);
     tableFrame->SetGeometryDirty();
   }
   return NS_OK;
 }
 nsresult
 nsTableRowGroupFrame::RemoveFrame(ChildListID     aListID,
                                   nsIFrame*       aOldFrame)
 {
   NS_ASSERTION(aListID == kPrincipalList, "unexpected child list");
   ClearRowCursor();
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   // XXX why are we doing the QI stuff?  There shouldn't be any non-rows here.
   nsTableRowFrame* rowFrame = do_QueryFrame(aOldFrame);
   if (rowFrame) {
     // remove the rows from the table (and flag a rebalance)
     tableFrame->RemoveRows(*rowFrame, 1, true);
     PresContext()->PresShell()->
       FrameNeedsReflow(this, nsIPresShell::eTreeChange,
                        NS_FRAME_HAS_DIRTY_CHILDREN);
     tableFrame->SetGeometryDirty();
   }
   mFrames.DestroyFrame(aOldFrame);
   return NS_OK;
 }
 /* virtual */ nsMargin
 nsTableRowGroupFrame::GetUsedMargin() const
 {
   return nsMargin(0,0,0,0);
 }
 /* virtual */ nsMargin
 nsTableRowGroupFrame::GetUsedBorder() const
 {
   return nsMargin(0,0,0,0);
 }
 /* virtual */ nsMargin
 nsTableRowGroupFrame::GetUsedPadding() const
 {
   return nsMargin(0,0,0,0);
 }
 nscoord
 nsTableRowGroupFrame::GetHeightBasis(const nsHTMLReflowState& aReflowState)
 {
   nscoord result = 0;
   nsTableFrame* tableFrame = nsTableFrame::GetTableFrame(this);
   if ((aReflowState.ComputedHeight() > 0) && (aReflowState.ComputedHeight() < NS_UNCONSTRAINEDSIZE)) {
     nscoord cellSpacing = std::max(0, GetRowCount() - 1) * tableFrame->GetCellSpacingY();
     result = aReflowState.ComputedHeight() - cellSpacing;
   }
   else {
     const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
     if (parentRS && (tableFrame != parentRS->frame)) {
       parentRS = parentRS->parentReflowState;
     }
     if (parentRS && (tableFrame == parentRS->frame) &&
         (parentRS->ComputedHeight() > 0) && (parentRS->ComputedHeight() < NS_UNCONSTRAINEDSIZE)) {
       nscoord cellSpacing = std::max(0, tableFrame->GetRowCount() + 1) * tableFrame->GetCellSpacingY();
       result = parentRS->ComputedHeight() - cellSpacing;
     }
   }
   return result;
 }
 bool
 nsTableRowGroupFrame::IsSimpleRowFrame(nsTableFrame* aTableFrame,
                                        nsIFrame*     aFrame)
 {
   // Make sure it's a row frame and not a row group frame
   nsTableRowFrame *rowFrame = do_QueryFrame(aFrame);
   if (rowFrame) {
     int32_t rowIndex = rowFrame->GetRowIndex();
     // It's a simple row frame if there are no cells that span into or
     // across the row
     int32_t numEffCols = aTableFrame->GetEffectiveColCount();
     if (!aTableFrame->RowIsSpannedInto(rowIndex, numEffCols) &&
         !aTableFrame->RowHasSpanningCells(rowIndex, numEffCols)) {
       return true;
     }
   }
   return false;
 }
 nsIAtom*
 nsTableRowGroupFrame::GetType() const
 {
   return nsGkAtoms::tableRowGroupFrame;
 }
 /** find page break before the first row **/
 bool
 nsTableRowGroupFrame::HasInternalBreakBefore() const
 {
  nsIFrame* firstChild = mFrames.FirstChild();
   if (!firstChild)
     return false;
   return firstChild->StyleDisplay()->mBreakBefore;
 }
 /** find page break after the last row **/
 bool
 nsTableRowGroupFrame::HasInternalBreakAfter() const
 {
   nsIFrame* lastChild = mFrames.LastChild();
   if (!lastChild)
     return false;
   return lastChild->StyleDisplay()->mBreakAfter;
 }
 /* ----- global methods ----- */
 nsIFrame*
 NS_NewTableRowGroupFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
 {
   return new (aPresShell) nsTableRowGroupFrame(aContext);
 }
 NS_IMPL_FRAMEARENA_HELPERS(nsTableRowGroupFrame)
 #ifdef DEBUG_FRAME_DUMP
 nsresult
 nsTableRowGroupFrame::GetFrameName(nsAString& aResult) const
 {
   return MakeFrameName(NS_LITERAL_STRING("TableRowGroup"), aResult);
 }
 #endif
 nsMargin*
 nsTableRowGroupFrame::GetBCBorderWidth(nsMargin& aBorder)
 {
   aBorder.left = aBorder.right = aBorder.top = aBorder.bottom = 0;
   nsTableRowFrame* firstRowFrame = nullptr;
   nsTableRowFrame* lastRowFrame = nullptr;
   for (nsTableRowFrame* rowFrame = GetFirstRow(); rowFrame; rowFrame = rowFrame->GetNextRow()) {
     if (!firstRowFrame) {
       firstRowFrame = rowFrame;
     }
     lastRowFrame = rowFrame;
   }
   if (firstRowFrame) {
     aBorder.top    = nsPresContext::CSSPixelsToAppUnits(firstRowFrame->GetTopBCBorderWidth());
     aBorder.bottom = nsPresContext::CSSPixelsToAppUnits(lastRowFrame->GetBottomBCBorderWidth());
   }
   return &aBorder;
 }
 void nsTableRowGroupFrame::SetContinuousBCBorderWidth(uint8_t     aForSide,
                                                       BCPixelSize aPixelValue)
 {
   switch (aForSide) {
     case NS_SIDE_RIGHT:
       mRightContBorderWidth = aPixelValue;
       return;
     case NS_SIDE_BOTTOM:
       mBottomContBorderWidth = aPixelValue;
       return;
     case NS_SIDE_LEFT:
       mLeftContBorderWidth = aPixelValue;
       return;
     default:
       NS_ERROR("invalid NS_SIDE argument");
   }
 }
 //nsILineIterator methods
 int32_t
 nsTableRowGroupFrame::GetNumLines()
 {
   return GetRowCount();
 }
 bool
 nsTableRowGroupFrame::GetDirection()
 {
   nsTableFrame* table = nsTableFrame::GetTableFrame(this);
   return (NS_STYLE_DIRECTION_RTL ==
           table->StyleVisibility()->mDirection);
 }
 NS_IMETHODIMP
 nsTableRowGroupFrame::GetLine(int32_t    aLineNumber,
                               nsIFrame** aFirstFrameOnLine,
                               int32_t*   aNumFramesOnLine,
                               nsRect&    aLineBounds,
                               uint32_t*  aLineFlags)
 {
   NS_ENSURE_ARG_POINTER(aFirstFrameOnLine);
   NS_ENSURE_ARG_POINTER(aNumFramesOnLine);
   NS_ENSURE_ARG_POINTER(aLineFlags);
   nsTableFrame* table = nsTableFrame::GetTableFrame(this);
   nsTableCellMap* cellMap = table->GetCellMap();
   *aLineFlags = 0;
   *aFirstFrameOnLine = nullptr;
   *aNumFramesOnLine = 0;
   aLineBounds.SetRect(0, 0, 0, 0);
   if ((aLineNumber < 0) || (aLineNumber >=  GetRowCount())) {
     return NS_OK;
   }
   aLineNumber += GetStartRowIndex();
   *aNumFramesOnLine = cellMap->GetNumCellsOriginatingInRow(aLineNumber);
   if (*aNumFramesOnLine == 0) {
     return NS_OK;
   }
   int32_t colCount = table->GetColCount();
   for (int32_t i = 0; i < colCount; i++) {
     CellData* data = cellMap->GetDataAt(aLineNumber, i);
     if (data && data->IsOrig()) {
       *aFirstFrameOnLine = (nsIFrame*)data->GetCellFrame();
       nsIFrame* parent = (*aFirstFrameOnLine)->GetParent();
       aLineBounds = parent->GetRect();
       return NS_OK;
     }
   }
   NS_ERROR("cellmap is lying");
   return NS_ERROR_FAILURE;
 }
 int32_t
 nsTableRowGroupFrame::FindLineContaining(nsIFrame* aFrame, int32_t aStartLine)
 {
   NS_ENSURE_TRUE(aFrame, -1);
   nsTableRowFrame *rowFrame = do_QueryFrame(aFrame);
   NS_ASSERTION(rowFrame, "RowGroup contains a frame that is not a row");
   int32_t rowIndexInGroup = rowFrame->GetRowIndex() - GetStartRowIndex();
   return rowIndexInGroup >= aStartLine ? rowIndexInGroup : -1;
 }
 NS_IMETHODIMP
 nsTableRowGroupFrame::CheckLineOrder(int32_t                  aLine,
                                      bool                     *aIsReordered,
                                      nsIFrame                 **aFirstVisual,
                                      nsIFrame                 **aLastVisual)
 {
   *aIsReordered = false;
   *aFirstVisual = nullptr;
   *aLastVisual = nullptr;
   return NS_OK;
 }
 NS_IMETHODIMP
 nsTableRowGroupFrame::FindFrameAt(int32_t    aLineNumber,
                                   nscoord    aX,
                                   nsIFrame** aFrameFound,
                                   bool*    aXIsBeforeFirstFrame,
                                   bool*    aXIsAfterLastFrame)
 {
    nsTableFrame* table = nsTableFrame::GetTableFrame(this);
    nsTableCellMap* cellMap = table->GetCellMap();
    *aFrameFound = nullptr;
    *aXIsBeforeFirstFrame = true;
    *aXIsAfterLastFrame = false;
    aLineNumber += GetStartRowIndex();
    int32_t numCells = cellMap->GetNumCellsOriginatingInRow(aLineNumber);
    if (numCells == 0) {
      return NS_OK;
    }
    nsIFrame* frame = nullptr;
    int32_t colCount = table->GetColCount();
    for (int32_t i = 0; i < colCount; i++) {
      CellData* data = cellMap->GetDataAt(aLineNumber, i);
      if (data && data->IsOrig()) {
        frame = (nsIFrame*)data->GetCellFrame();
        break;
      }
    }
    NS_ASSERTION(frame, "cellmap is lying");
    bool isRTL = (NS_STYLE_DIRECTION_RTL ==
                    table->StyleVisibility()->mDirection);
    nsIFrame* closestFromLeft = nullptr;
    nsIFrame* closestFromRight = nullptr;
    int32_t n = numCells;
    nsIFrame* firstFrame = frame;
    while (n--) {
      nsRect rect = frame->GetRect();
      if (rect.width > 0) {
        // If aX is inside this frame - this is it
        if (rect.x <= aX && rect.XMost() > aX) {
          closestFromLeft = closestFromRight = frame;
          break;
        }
        if (rect.x < aX) {
          if (!closestFromLeft ||
              rect.XMost() > closestFromLeft->GetRect().XMost())
            closestFromLeft = frame;
        }
        else {
          if (!closestFromRight ||
              rect.x < closestFromRight->GetRect().x)
            closestFromRight = frame;
        }
      }
      frame = frame->GetNextSibling();
    }
    if (!closestFromLeft && !closestFromRight) {
      // All frames were zero-width. Just take the first one.
      closestFromLeft = closestFromRight = firstFrame;
    }
    *aXIsBeforeFirstFrame = isRTL ? !closestFromRight : !closestFromLeft;
    *aXIsAfterLastFrame =   isRTL ? !closestFromLeft : !closestFromRight;
    if (closestFromLeft == closestFromRight) {
      *aFrameFound = closestFromLeft;
    }
    else if (!closestFromLeft) {
      *aFrameFound = closestFromRight;
    }
    else if (!closestFromRight) {
      *aFrameFound = closestFromLeft;
    }
    else { // we're between two frames
      nscoord delta = closestFromRight->GetRect().x -
                      closestFromLeft->GetRect().XMost();
      if (aX < closestFromLeft->GetRect().XMost() + delta/2)
        *aFrameFound = closestFromLeft;
      else
        *aFrameFound = closestFromRight;
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsTableRowGroupFrame::GetNextSiblingOnLine(nsIFrame*& aFrame,
                                            int32_t    aLineNumber)
 {
   NS_ENSURE_ARG_POINTER(aFrame);
   aFrame = aFrame->GetNextSibling();
   return NS_OK;
 }
 //end nsLineIterator methods
 static void
 DestroyFrameCursorData(void* aPropertyValue)
 {
   delete static_cast<nsTableRowGroupFrame::FrameCursorData*>(aPropertyValue);
 }
 NS_DECLARE_FRAME_PROPERTY(RowCursorProperty, DestroyFrameCursorData)
 void
 nsTableRowGroupFrame::ClearRowCursor()
 {
   if (!(GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR))
     return;
   RemoveStateBits(NS_ROWGROUP_HAS_ROW_CURSOR);
   Properties().Delete(RowCursorProperty());
 }
 nsTableRowGroupFrame::FrameCursorData*
 nsTableRowGroupFrame::SetupRowCursor()
 {
   if (GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR) {
     // We already have a valid row cursor. Don't waste time rebuilding it.
     return nullptr;
   }
   nsIFrame* f = mFrames.FirstChild();
   int32_t count;
   for (count = 0; f && count < MIN_ROWS_NEEDING_CURSOR; ++count) {
     f = f->GetNextSibling();
   }
   if (!f) {
     // Less than MIN_ROWS_NEEDING_CURSOR rows, so just don't bother
     return nullptr;
   }
   FrameCursorData* data = new FrameCursorData();
   if (!data)
     return nullptr;
   Properties().Set(RowCursorProperty(), data);
   AddStateBits(NS_ROWGROUP_HAS_ROW_CURSOR);
   return data;
 }
 nsIFrame*
 nsTableRowGroupFrame::GetFirstRowContaining(nscoord aY, nscoord* aOverflowAbove)
 {
   if (!(GetStateBits() & NS_ROWGROUP_HAS_ROW_CURSOR))
     return nullptr;
   FrameCursorData* property = static_cast<FrameCursorData*>
     (Properties().Get(RowCursorProperty()));
   uint32_t cursorIndex = property->mCursorIndex;
   uint32_t frameCount = property->mFrames.Length();
   if (cursorIndex >= frameCount)
     return nullptr;
   nsIFrame* cursorFrame = property->mFrames[cursorIndex];
   // The cursor's frame list excludes frames with empty overflow-area, so
   // we don't need to check that here.
   // We use property->mOverflowBelow here instead of computing the frame's
   // true overflowArea.YMost(), because it is essential for the thresholds
   // to form a monotonically increasing sequence. Otherwise we would break
   // encountering a row whose overflowArea.YMost() is <= aY but which has
   // a row above it containing cell(s) that span to include aY.
   while (cursorIndex > 0 &&
          cursorFrame->GetRect().YMost() + property->mOverflowBelow > aY) {
     --cursorIndex;
     cursorFrame = property->mFrames[cursorIndex];
   }
   while (cursorIndex + 1 < frameCount &&
          cursorFrame->GetRect().YMost() + property->mOverflowBelow <= aY) {
     ++cursorIndex;
     cursorFrame = property->mFrames[cursorIndex];
   }
   property->mCursorIndex = cursorIndex;
   *aOverflowAbove = property->mOverflowAbove;
   return cursorFrame;
 }
 bool
 nsTableRowGroupFrame::FrameCursorData::AppendFrame(nsIFrame* aFrame)
 {
   nsRect overflowRect = aFrame->GetVisualOverflowRect();
   if (overflowRect.IsEmpty())
     return true;
   nscoord overflowAbove = -overflowRect.y;
   nscoord overflowBelow = overflowRect.YMost() - aFrame->GetSize().height;
   mOverflowAbove = std::max(mOverflowAbove, overflowAbove);
   mOverflowBelow = std::max(mOverflowBelow, overflowBelow);
   return mFrames.AppendElement(aFrame) != nullptr;
 }
 void
 nsTableRowGroupFrame::InvalidateFrame(uint32_t aDisplayItemKey)
 {
   nsIFrame::InvalidateFrame(aDisplayItemKey);
   GetParent()->InvalidateFrameWithRect(GetVisualOverflowRect() + GetPosition(), aDisplayItemKey);
 }
 void
 nsTableRowGroupFrame::InvalidateFrameWithRect(const nsRect& aRect, uint32_t aDisplayItemKey)
 {
   nsIFrame::InvalidateFrameWithRect(aRect, aDisplayItemKey);
   // If we have filters applied that would affects our bounds, then
   // we get an inactive layer created and this is computed
   // within FrameLayerBuilder
   GetParent()->InvalidateFrameWithRect(aRect + GetPosition(), aDisplayItemKey);
 }

The Tor Browser / annotate

layout/tables/nsTableRowGroupFrame.cpp@44a2da4a2ab2 (annotated)

layout/tables/nsTableRowGroupFrame.cpp