Add handling for Skia's SkPath::intersect's return value

chrome/browser/ui/views/tabs/tab.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/tabs/tab.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/debug/alias.h"
@@ skipping 692 matching lines @@
       widget && (widget->IsMaximized() || widget->IsFullscreen());
   TabResources::GetHitTestMask(width(), height(), include_top_shadow, mask);
 
   // It is possible for a portion of the tab to be occluded if tabs are
   // stacked, so modify the hit test mask to only include the visible
   // region of the tab.
   gfx::Rect clip;
   controller_->ShouldPaintTab(this, &clip);
   if (clip.size().GetArea()) {
     SkRect intersection(mask->getBounds());
-    intersection.intersect(RectToSkRect(clip));
     mask->reset();
-    mask->addRect(intersection);
+    if (intersection.intersect(RectToSkRect(clip))) {

[sky, 2015/01/05 16:32:44]

If the two don't intersect, then I think this function should return false.

[tdanderson, 2015/01/05 17:16:43]

I agree. Change the block starting at line 711 to this:

if (clip.size().GetArea()) {
  SkRect intersection(mask->getBounds());
  mask->reset();
  if (!intersection.intersect(RectToSkRect(clip)))
    return false;
  mask->addRect(intersection);
}

[robertphillips, 2015/01/05 19:31:56]

Done.

+      mask->addRect(intersection);
+    }
   }
 
   return true;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // Tab, views::View overrides:
 
 void Tab::OnPaint(gfx::Canvas* canvas) {
   // Don't paint if we're narrower than we can render correctly. (This should
@@ skipping 873 matching lines @@
                          const gfx::ImageSkia& image) {
   DCHECK_NE(scale_factor, ui::SCALE_FACTOR_NONE);
   ImageCacheEntry entry;
   entry.resource_id = resource_id;
   entry.scale_factor = scale_factor;
   entry.image = image;
   image_cache_->push_front(entry);
   if (image_cache_->size() > kMaxImageCacheSize)
     image_cache_->pop_back();
 }