Check scrollbars before hit testing border radius

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
@@ skipping 1611 matching lines @@
     }
 
     return false;
 }
 
 bool LayoutBlock::hitTestChildren(HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction hitTestAction)
 {
     // TODO(pdr): We should also check for css clip in the !isSelfPaintingLayer
     //            case, similar to overflow clip below.
     if (hasOverflowClip() && !hasSelfPaintingLayer()) {
+        if (!locationInContainer.intersects(overflowClipRect(accumulatedOffset, IncludeOverlayScrollbarSize)))

[chrishtr, 2016/04/18 16:17:38]

When would overflowClipRect(...) be smaller than
style()->getRoundedInnerBorderFor(...) below? Related to my other comment.

+            return false;
         if (style()->hasBorderRadius()) {
             LayoutRect borderRect = borderBoxRect();
             borderRect.moveBy(accumulatedOffset);
             if (!locationInContainer.intersects(style()->getRoundedInnerBorderFor(borderRect)))
                 return false;
-        } else {
-            if (!locationInContainer.intersects(overflowClipRect(accumulatedOffset, IncludeOverlayScrollbarSize)))
-                return false;
         }
     }
 
     // A control clip can also clip out child hit testing.
     if (hasControlClip() && !locationInContainer.intersects(controlClipRect(accumulatedOffset)))
         return false;
 
     LayoutPoint scrolledOffset(hasOverflowClip() ? accumulatedOffset - scrolledContentOffset() : accumulatedOffset);
     if (childrenInline() && !isTable()) {
         if (m_lineBoxes.hitTest(LineLayoutBoxModel(this), result, locationInContainer, scrolledOffset, hitTestAction)) {
@@ skipping 1183 matching lines @@
 void LayoutBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const LayoutObject* obj) const
 {
     showLayoutObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink