Advance document lifecycle to CompositingClean prior to hit testing

Source/core/layout/LayoutView.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 79 matching lines @@
     m_hitTestCount++;
 
     ASSERT(!location.isRectBasedTest() || request.listBased());
 
     // We have to recursively update layout/style here because otherwise, when the hit test recurses
     // into a child document, it could trigger a layout on the parent document, which can destroy Layers
     // that are higher up in the call stack, leading to crashes.
     // Note that Document::updateLayout calls its parent's updateLayout.
     // FIXME: It should be the caller's responsibility to ensure an up-to-date layout.
     frameView()->updateLayoutAndStyleIfNeededRecursive();
+    compositor()->updateIfNeededRecursive();
     commitPendingSelection();
+    ASSERT(document().lifecycle().state() >= DocumentLifecycle::CompositingClean);

[leviw_travelin_and_unemployed, 2015/03/12 20:09:32]

This assert should go somewhere deeper in Blink, like Layer::hitTestLayer

[qiankun, 2015/03/13 03:23:10]

Done.

 
     bool hitLayer = layer()->hitTest(request, location, result);
 
     // FrameView scrollbars are not the same as Layer scrollbars tested by Layer::hitTestOverflowControls,
     // so we need to test FrameView scrollbars separately here. Note that it's important we do this after
     // the hit test above, because that may overwrite the entire HitTestResult when it finds a hit.
     IntPoint framePoint = frameView()->contentsToFrame(location.roundedPoint());
     if (Scrollbar* frameScrollbar = frameView()->scrollbarAtFramePoint(framePoint))
         result.setScrollbar(frameScrollbar);
 
@@ skipping 875 matching lines @@
     return viewHeight(IncludeScrollbars) / scale;
 }
 
 void LayoutView::willBeDestroyed()
 {
     LayoutBlockFlow::willBeDestroyed();
     m_compositor.clear();
 }
 
 } // namespace blink