Add a hack to set shouldPaint to true for force-composited iframes.

third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 3263 matching lines @@
         LayoutUnit logicalBottomForFloat = std::min(this->logicalBottomForFloat(floatingObject), LayoutUnit::max() - childLogicalTop);
         LayoutUnit logicalBottom = childLogicalTop + logicalBottomForFloat;
 
         if (logicalBottom > logicalHeight()) {
             // If the object is not in the list, we add it now.
             if (!containsFloat(floatingObject.layoutObject())) {
                 LayoutSize offset = isHorizontalWritingMode() ? LayoutSize(-childLogicalLeft, -childLogicalTop) : LayoutSize(-childLogicalTop, -childLogicalLeft);
                 bool shouldPaint = false;
 
                 // The nearest enclosing layer always paints the float (so that zindex and stacking
-                // behaves properly). We always want to propagate the desire to paint the float as
+            // behaves properly). We always want to propagate the desire to paint the float as

[Xianzhu, 2016/05/26 18:29:54]

Nit: Unnecessary change

[chrishtr, 2016/05/26 18:49:29]

Done.

                 // far out as we can, to the outermost block that overlaps the float, stopping only
                 // if we hit a self-painting layer boundary.
                 if (floatingObject.layoutObject()->enclosingFloatPaintingLayer() == enclosingFloatPaintingLayer() && !floatingObject.isLowestNonOverhangingFloatInChild()) {
                     floatingObject.setShouldPaint(false);
                     shouldPaint = true;
                 }
                 // We create the floating object list lazily.
                 if (!m_floatingObjects)
                     createFloatingObjects();
 
@@ skipping 76 matching lines @@
     if (isLayoutView()) {
         DoublePoint position = toLayoutView(this)->frameView()->scrollPositionDouble();
         adjustedLocation.move(position.x(), position.y());
     }
 
     const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
     FloatingObjectSetIterator begin = floatingObjectSet.begin();
     for (FloatingObjectSetIterator it = floatingObjectSet.end(); it != begin;) {
         --it;
         const FloatingObject& floatingObject = *it->get();
-        if (floatingObject.shouldPaint() && !floatingObject.layoutObject()->hasSelfPaintingLayer()) {
+        if (floatingObject.shouldPaint()) {
             LayoutUnit xOffset = xPositionForFloatIncludingMargin(floatingObject) - floatingObject.layoutObject()->location().x();
             LayoutUnit yOffset = yPositionForFloatIncludingMargin(floatingObject) - floatingObject.layoutObject()->location().y();
             LayoutPoint childPoint = flipFloatForWritingModeForChild(floatingObject, adjustedLocation + LayoutSize(xOffset, yOffset));
             if (floatingObject.layoutObject()->hitTest(result, locationInContainer, childPoint)) {
                 updateHitTestResult(result, locationInContainer.point() - toLayoutSize(childPoint));
                 return true;
             }
         }
     }
 
@@ skipping 458 matching lines @@
             if (!rect.isEmpty())
                 rects.append(rect);
         }
     }
 
     if (inlineElementContinuation)
         inlineElementContinuation->addOutlineRects(rects, additionalOffset + (inlineElementContinuation->containingBlock()->location() - location()), includeBlockOverflows);
 }
 
 } // namespace blink