diff -r 000000000000 -r 6474c204b198 layout/mathml/nsMathMLSelectedFrame.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/mathml/nsMathMLSelectedFrame.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,154 @@
+/* -*- 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 "nsMathMLSelectedFrame.h"
+#include "nsDisplayList.h"
+
+nsMathMLSelectedFrame::~nsMathMLSelectedFrame()
+{
+}
+
+void
+nsMathMLSelectedFrame::Init(nsIContent*      aContent,
+                            nsIFrame*        aParent,
+                            nsIFrame*        aPrevInFlow)
+{
+  // Init our local attributes
+  mInvalidMarkup = false;
+  mSelectedFrame = nullptr;
+
+  // Let the base class do the rest
+  nsMathMLContainerFrame::Init(aContent, aParent, aPrevInFlow);
+}
+
+NS_IMETHODIMP
+nsMathMLSelectedFrame::TransmitAutomaticData()
+{
+  // Note that to determine space-like and embellished op properties:
+  //   - <semantics> behaves the same as <maction>
+  //   - <annotation-xml> behaves the same as <mrow>
+
+  // The REC defines the following element to be space-like:
+  // * an maction element whose selected sub-expression exists and is
+  //   space-like;
+  nsIMathMLFrame* mathMLFrame = do_QueryFrame(mSelectedFrame);
+  if (mathMLFrame && mathMLFrame->IsSpaceLike()) {
+    mPresentationData.flags |= NS_MATHML_SPACE_LIKE;
+  } else {
+    mPresentationData.flags &= ~NS_MATHML_SPACE_LIKE;
+  }
+
+  // The REC defines the following element to be an embellished operator:
+  // * an maction element whose selected sub-expression exists and is an
+  //   embellished operator;
+  mPresentationData.baseFrame = mSelectedFrame;
+  GetEmbellishDataFrom(mSelectedFrame, mEmbellishData);
+
+  return NS_OK;
+}
+
+nsresult
+nsMathMLSelectedFrame::ChildListChanged(int32_t aModType)
+{
+  GetSelectedFrame();
+  return nsMathMLContainerFrame::ChildListChanged(aModType);
+}
+
+nsresult
+nsMathMLSelectedFrame::SetInitialChildList(ChildListID     aListID,
+                                           nsFrameList&    aChildList)
+{
+  nsresult rv = nsMathMLContainerFrame::SetInitialChildList(aListID,
+                                                            aChildList);
+  // This very first call to GetSelectedFrame() will cause us to be marked as an
+  // embellished operator if the selected child is an embellished operator
+  GetSelectedFrame();
+  return rv;
+}
+
+//  Only paint the selected child...
+void
+nsMathMLSelectedFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
+                                        const nsRect&           aDirtyRect,
+                                        const nsDisplayListSet& aLists)
+{
+  // Report an error if something wrong was found in this frame.
+  // We can't call nsDisplayMathMLError from here,
+  // so ask nsMathMLContainerFrame to do the work for us.
+  if (NS_MATHML_HAS_ERROR(mPresentationData.flags)) {
+    nsMathMLContainerFrame::BuildDisplayList(aBuilder, aDirtyRect, aLists);
+    return;
+  }
+
+  DisplayBorderBackgroundOutline(aBuilder, aLists);
+
+  nsIFrame* childFrame = GetSelectedFrame();
+  if (childFrame) {
+    // Put the child's background directly onto the content list
+    nsDisplayListSet set(aLists, aLists.Content());
+    // The children should be in content order
+    BuildDisplayListForChild(aBuilder, childFrame, aDirtyRect, set);
+  }
+
+#if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
+  // visual debug
+  DisplayBoundingMetrics(aBuilder, this, mReference, mBoundingMetrics, aLists);
+#endif
+}
+
+// Only reflow the selected child ...
+nsresult
+nsMathMLSelectedFrame::Reflow(nsPresContext*          aPresContext,
+                              nsHTMLReflowMetrics&     aDesiredSize,
+                              const nsHTMLReflowState& aReflowState,
+                              nsReflowStatus&          aStatus)
+{
+  nsresult rv = NS_OK;
+  aStatus = NS_FRAME_COMPLETE;
+  aDesiredSize.Width() = aDesiredSize.Height() = 0;
+  aDesiredSize.SetTopAscent(0);
+  mBoundingMetrics = nsBoundingMetrics();
+  nsIFrame* childFrame = GetSelectedFrame();
+  if (childFrame) {
+    nsSize availSize(aReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE);
+    nsHTMLReflowState childReflowState(aPresContext, aReflowState,
+                                       childFrame, availSize);
+    rv = ReflowChild(childFrame, aPresContext, aDesiredSize,
+                     childReflowState, aStatus);
+    SaveReflowAndBoundingMetricsFor(childFrame, aDesiredSize,
+                                    aDesiredSize.mBoundingMetrics);
+    mBoundingMetrics = aDesiredSize.mBoundingMetrics;
+  }
+  FinalizeReflow(*aReflowState.rendContext, aDesiredSize);
+  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
+  return rv;
+}
+
+// Only place the selected child ...
+/* virtual */ nsresult
+nsMathMLSelectedFrame::Place(nsRenderingContext& aRenderingContext,
+                             bool                 aPlaceOrigin,
+                             nsHTMLReflowMetrics& aDesiredSize)
+{
+  nsIFrame* childFrame = GetSelectedFrame();
+
+  if (mInvalidMarkup) {
+    return ReflowError(aRenderingContext, aDesiredSize);
+  }
+
+  aDesiredSize.Width() = aDesiredSize.Height() = 0;
+  aDesiredSize.SetTopAscent(0);
+  mBoundingMetrics = nsBoundingMetrics();
+  if (childFrame) {
+    GetReflowAndBoundingMetricsFor(childFrame, aDesiredSize, mBoundingMetrics);
+    if (aPlaceOrigin) {
+      FinishReflowChild(childFrame, PresContext(), aDesiredSize, nullptr, 0, 0, 0);
+    }
+    mReference.x = 0;
+    mReference.y = aDesiredSize.TopAscent();
+  }
+  aDesiredSize.mBoundingMetrics = mBoundingMetrics;
+  return NS_OK;
+}