Combine LayoutObject::previousPaintOffset and paintOffset in paint properties

third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp

Index: third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp
diff --git a/third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp b/third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp
index 7d803026e7f88ce390d0924ebaecc74086bdf79c..fdea498252671b72546b129a55cfe06b66c71a88 100644
--- a/third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp
+++ b/third_party/WebKit/Source/core/paint/PrePaintTreeWalk.cpp
@@ -128,6 +128,7 @@ bool PrePaintTreeWalk::walk(const LayoutObject& object,
   // Ensure the current context takes into account the box's position. This can
   // force a subtree update due to paint offset changes and must precede any
   // early out from the treewalk.
+  LayoutPoint oldPaintOffset = object.paintOffset();
   m_propertyTreeBuilder.updateContextForBoxPosition(object,
                                                     context.treeBuilderContext);
 
@@ -145,7 +146,7 @@ bool PrePaintTreeWalk::walk(const LayoutObject& object,
 
   m_propertyTreeBuilder.updatePropertiesForSelf(object,
                                                 context.treeBuilderContext);
-  m_paintInvalidator.invalidatePaintIfNeeded(object,
+  m_paintInvalidator.invalidatePaintIfNeeded(object, oldPaintOffset,
                                              context.paintInvalidatorContext);
   m_propertyTreeBuilder.updatePropertiesForChildren(object,
                                                     context.treeBuilderContext);