Don't add empty rects during addFocusRingRects

Source/core/rendering/RenderInline.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 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.
  *
@@ skipping 1345 matching lines @@
 
 void RenderInline::imageChanged(WrappedImagePtr, const IntRect*)
 {
     if (!parent())
         return;
 
     // FIXME: We can do better.
     setShouldDoFullPaintInvalidation(true);
 }
 
+namespace {

[esprehn, 2014/08/21 17:22:08]

No need for the anonymous namespace. Also why wouldn't the normal
AbsoluteRectsGeneratorContext want to ignore empty rects?

[Xianzhu, 2014/08/21 17:26:28]

I saw yield(FloatRect()) in the code, so wondering if keeping empty rects is
intentional for other GeneratorContext users. I can investigate on this.

[Xianzhu, 2014/08/22 00:12:15]

Tried to ignore empty rects for all GeneratorContext users, ran layout tests and
got several failures. The empty rects seem to be needed by the other
GeneratorContext users to behave correctly. So for focus rings, we do need a
special GeneratorContext to ignore the empty rects.

+
+class AbsoluteRectsIgnoringEmptyRectsGeneratorContext : public AbsoluteRectsGeneratorContext {
+public:
+    AbsoluteRectsIgnoringEmptyRectsGeneratorContext(Vector<IntRect>& rects, const LayoutPoint& accumulatedOffset)
+        : AbsoluteRectsGeneratorContext(rects, accumulatedOffset) { }
+
+    void operator()(const FloatRect& rect)
+    {
+        if (!rect.isEmpty())
+            AbsoluteRectsGeneratorContext::operator()(rect);
+    }
+};
+
+} // unnamed namespace
+
 void RenderInline::addFocusRingRects(Vector<IntRect>& rects, const LayoutPoint& additionalOffset, const RenderLayerModelObject* paintContainer) const
 {
-    AbsoluteRectsGeneratorContext context(rects, additionalOffset);
+    AbsoluteRectsIgnoringEmptyRectsGeneratorContext context(rects, additionalOffset);
     generateLineBoxRects(context);
 
     addChildFocusRingRects(rects, additionalOffset, paintContainer);
 
     if (continuation()) {
         // If the continuation doesn't paint into the same container, let its paint invalidation container handle it.
         if (paintContainer != continuation()->containerForPaintInvalidation())
             return;
         if (continuation()->isInline())
             continuation()->addFocusRingRects(rects, flooredLayoutPoint(additionalOffset + continuation()->containingBlock()->location() - containingBlock()->location()), paintContainer);
@@ skipping 201 matching lines @@
         container = this;
 
     FloatPoint absPos = container->localToAbsolute();
     region.bounds.setX(absPos.x() + region.bounds.x());
     region.bounds.setY(absPos.y() + region.bounds.y());
 
     regions.append(region);
 }
 
 } // namespace blink