diff -r 000000000000 -r 6474c204b198 layout/forms/nsGfxCheckboxControlFrame.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/forms/nsGfxCheckboxControlFrame.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,135 @@
+/* -*- 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 "nsGfxCheckboxControlFrame.h"
+#include "nsIContent.h"
+#include "nsCOMPtr.h"
+#include "nsRenderingContext.h"
+#include "nsIDOMHTMLInputElement.h"
+#include "nsDisplayList.h"
+#include <algorithm>
+
+using namespace mozilla;
+
+static void
+PaintCheckMark(nsIFrame* aFrame,
+               nsRenderingContext* aCtx,
+               const nsRect& aDirtyRect,
+               nsPoint aPt)
+{
+  nsRect rect(aPt, aFrame->GetSize());
+  rect.Deflate(aFrame->GetUsedBorderAndPadding());
+
+  // Points come from the coordinates on a 7X7 unit box centered at 0,0
+  const int32_t checkPolygonX[] = { -3, -1,  3,  3, -1, -3 };
+  const int32_t checkPolygonY[] = { -1,  1, -3, -1,  3,  1 };
+  const int32_t checkNumPoints = sizeof(checkPolygonX) / sizeof(int32_t);
+  const int32_t checkSize      = 9; // 2 units of padding on either side
+                                    // of the 7x7 unit checkmark
+
+  // Scale the checkmark based on the smallest dimension
+  nscoord paintScale = std::min(rect.width, rect.height) / checkSize;
+  nsPoint paintCenter(rect.x + rect.width  / 2,
+                      rect.y + rect.height / 2);
+
+  nsPoint paintPolygon[checkNumPoints];
+  // Convert checkmark for screen rendering
+  for (int32_t polyIndex = 0; polyIndex < checkNumPoints; polyIndex++) {
+    paintPolygon[polyIndex] = paintCenter +
+                              nsPoint(checkPolygonX[polyIndex] * paintScale,
+                                      checkPolygonY[polyIndex] * paintScale);
+  }
+
+  aCtx->SetColor(aFrame->StyleColor()->mColor);
+  aCtx->FillPolygon(paintPolygon, checkNumPoints);
+}
+
+static void
+PaintIndeterminateMark(nsIFrame* aFrame,
+                       nsRenderingContext* aCtx,
+                       const nsRect& aDirtyRect,
+                       nsPoint aPt)
+{
+  nsRect rect(aPt, aFrame->GetSize());
+  rect.Deflate(aFrame->GetUsedBorderAndPadding());
+
+  rect.y += (rect.height - rect.height/4) / 2;
+  rect.height /= 4;
+
+  aCtx->SetColor(aFrame->StyleColor()->mColor);
+  aCtx->FillRect(rect);
+}
+
+//------------------------------------------------------------
+nsIFrame*
+NS_NewGfxCheckboxControlFrame(nsIPresShell* aPresShell,
+                              nsStyleContext* aContext)
+{
+  return new (aPresShell) nsGfxCheckboxControlFrame(aContext);
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsGfxCheckboxControlFrame)
+
+
+//------------------------------------------------------------
+// Initialize GFX-rendered state
+nsGfxCheckboxControlFrame::nsGfxCheckboxControlFrame(nsStyleContext* aContext)
+: nsFormControlFrame(aContext)
+{
+}
+
+nsGfxCheckboxControlFrame::~nsGfxCheckboxControlFrame()
+{
+}
+
+#ifdef ACCESSIBILITY
+a11y::AccType
+nsGfxCheckboxControlFrame::AccessibleType()
+{
+  return a11y::eHTMLCheckboxType;
+}
+#endif
+
+//------------------------------------------------------------
+void
+nsGfxCheckboxControlFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
+                                            const nsRect&           aDirtyRect,
+                                            const nsDisplayListSet& aLists)
+{
+  nsFormControlFrame::BuildDisplayList(aBuilder, aDirtyRect, aLists);
+  
+  // Get current checked state through content model.
+  if ((!IsChecked() && !IsIndeterminate()) || !IsVisibleForPainting(aBuilder))
+    return;   // we're not checked or not visible, nothing to paint.
+    
+  if (IsThemed())
+    return; // No need to paint the checkmark. The theme will do it.
+
+  aLists.Content()->AppendNewToTop(new (aBuilder)
+    nsDisplayGeneric(aBuilder, this,
+                     IsIndeterminate()
+                     ? PaintIndeterminateMark : PaintCheckMark,
+                     "CheckedCheckbox",
+                     nsDisplayItem::TYPE_CHECKED_CHECKBOX));
+}
+
+//------------------------------------------------------------
+bool
+nsGfxCheckboxControlFrame::IsChecked()
+{
+  nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
+  bool retval = false;
+  elem->GetChecked(&retval);
+  return retval;
+}
+
+bool
+nsGfxCheckboxControlFrame::IsIndeterminate()
+{
+  nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
+  bool retval = false;
+  elem->GetIndeterminate(&retval);
+  return retval;
+}