Fix paint invalidation of paintInvalidationContainer itself

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 1883 matching lines @@
     // physical coordinate space of the paintInvalidationContainer.
     const ComputedStyle& styleToUse = styleRef();
 
     EPosition position = styleToUse.position();
 
     // We need to inflate the paint invalidation rect before we use paintInvalidationState,
     // else we would forget to inflate it for the current layoutObject. FIXME: If these were
     // included into the visual overflow for repaint, we wouldn't have this issue.
     inflatePaintInvalidationRectForReflectionAndFilter(rect);
 
+    // This condition should be put before the paintInvalidationState logic because the latter
+    // can't handle the case. We also can't let PaintInvalidationState handle the case, because
+    // this code is also needed when there is no PaintInvalidationState.

[chrishtr, 2016/03/11 22:11:44]

TODO(wangxianzhu): refactor to fix this code structure.

[Xianzhu, 2016/03/11 22:30:51]

Done.

+    if (ancestor == this) {
+        if (ancestor->style()->isFlippedBlocksWritingMode())
+            flipForWritingMode(rect);
+        return;
+    }
+
     if (paintInvalidationState && paintInvalidationState->canMapToContainer(ancestor) && position != FixedPosition) {
         if (layer() && layer()->transform())
             rect = LayoutRect(layer()->transform()->mapRect(pixelSnappedIntRect(rect)));
 
         // We can't trust the bits on LayoutObject, because this might be called while re-resolving style.
         if (styleToUse.hasInFlowPosition() && layer())
             rect.move(layer()->offsetForInFlowPosition());
 
         rect.moveBy(location());
         rect.move(paintInvalidationState->paintOffset());
         if (paintInvalidationState->isClipped())
             rect.intersect(paintInvalidationState->clipRect());
         return;
     }
 
-    if (ancestor == this) {
-        if (ancestor->style()->isFlippedBlocksWritingMode())
-            flipForWritingMode(rect);
-        return;
-    }
-
     bool containerSkipped;
     LayoutObject* container = this->container(ancestor, &containerSkipped);
     if (!container)
         return;
 
     if (isWritingModeRoot())
         flipForWritingMode(rect);
 
     LayoutPoint topLeft = rect.location();
     topLeft.move(locationOffset());
@@ skipping 2743 matching lines @@
 }
 
 void LayoutBox::IntrinsicSizingInfo::transpose()
 {
     size = size.transposedSize();
     aspectRatio = aspectRatio.transposedSize();
     std::swap(hasWidth, hasHeight);
 }
 
 } // namespace blink