Revert of Fix several corner case issues of scrollbar paint invalidation

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

Index: third_party/WebKit/Source/core/layout/LayoutObject.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutObject.cpp b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
index 8488d8811639a3b47cf28a90452a988fc2532ead..7f142f6b638696d8bc75913da0f0855cf9bdc626 100644
--- a/third_party/WebKit/Source/core/layout/LayoutObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
@@ -1517,11 +1517,6 @@
     m_previousPaintInvalidationRect.move(LayoutSize(scrollDelta));
 }
 
-void LayoutObject::clearPreviousPaintInvalidationRects()
-{
-    setPreviousPaintInvalidationRect(LayoutRect());
-}
-
 void LayoutObject::incrementallyInvalidatePaint(const LayoutBoxModelObject& paintInvalidationContainer, const LayoutRect& oldBounds, const LayoutRect& newBounds, const LayoutPoint& positionFromPaintInvalidationBacking)
 {
     ASSERT(oldBounds.location() == newBounds.location());
@@ -3428,7 +3423,7 @@
     // Clear previous paint invalidation rect on the original paint invalidation container to avoid
     // under-invalidation if the new paint invalidation rect on the new paint invalidation container
     // happens to be the same as the old one.
-    clearPreviousPaintInvalidationRects();
+    setPreviousPaintInvalidationRect(LayoutRect());
 }
 
 void LayoutObject::invalidatePaintIncludingNonCompositingDescendants()