Fix paint invalidation for composited vertical-rl having overflow

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

Index: third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp
diff --git a/third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp b/third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp
index d61e401ef28ecdcfb032ea4fa85d80dd354f6b01..192eb2a5a59bb0180e93b1f43708b3f9b21e828f 100644
--- a/third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp
+++ b/third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp
@@ -418,11 +418,8 @@ static void slowMapToVisualRectInAncestorSpace(const LayoutObject& object, const
     // TODO(wkorman): The flip below is required because visual rects are
     // currently in "physical coordinates with flipped block-flow direction"
     // (see LayoutBoxModelObject.h) but we need them to be in physical
-    // coordinates. When we're mapping within exactly one object we keep the
-    // input rect flipped because we'd just have to re-flip in short order, as
-    // the output of this method must be in the "physical coordinates with
-    // flipped block-flow direction.
-    if (object.isBox() && object != ancestor)
+    // coordinates.
+    if (object.isBox())
         toLayoutBox(&object)->flipForWritingMode(rect);
 
     if (object.isLayoutView())