Refactor LayoutInline::addOutlineRects to avoid tricky logic to avoid dups

Source/core/layout/LayoutBoxModelObject.cpp

Index: Source/core/layout/LayoutBoxModelObject.cpp
diff --git a/Source/core/layout/LayoutBoxModelObject.cpp b/Source/core/layout/LayoutBoxModelObject.cpp
index 322bb7e4a5ebb6323025e044c5ed1568a0ac6880..96bebfea7f0dcd84f47244740ac09f48c4d4c761 100644
--- a/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/Source/core/layout/LayoutBoxModelObject.cpp
@@ -414,6 +414,13 @@ void LayoutBoxModelObject::addOutlineRectsForDescendant(const LayoutObject& desc
         return;
     }
 
+    if (descendant.isLayoutInline()) {
+        // Some ancestor of the LayoutInline has already added outline rects for line boxes,

[chrishtr, 2015/08/10 20:14:47]

Add to this:

// The rects are computed by an ancestor as an optimization to avoid extra
computation for line boxes.
// In particular, LayoutBlock adds rects for its RootOutlineBoxes, which include
the bounds of this LayoutInline.

[Xianzhu, 2015/08/10 21:52:32]

Done.

+        // so the LayoutInline needs to add outline rects for children and continuations only.
+        toLayoutInline(descendant).addOutlineRectsForChildrenAndContinuations(rects, additionalOffset);
+        return;
+    }
+
     descendant.addOutlineRects(rects, additionalOffset);
 }