Don't add empty rects during addFocusRingRects

Source/core/rendering/RenderInline.cpp

Index: Source/core/rendering/RenderInline.cpp
diff --git a/Source/core/rendering/RenderInline.cpp b/Source/core/rendering/RenderInline.cpp
index 802732c0f5f72098f7cce116e6e11ae04e76402b..84539940e01b14f27012d0b2f89b355372b7377c 100644
--- a/Source/core/rendering/RenderInline.cpp
+++ b/Source/core/rendering/RenderInline.cpp
@@ -1363,9 +1363,25 @@ void RenderInline::imageChanged(WrappedImagePtr, const IntRect*)
     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);