Define contentsProperties on ObjectPaintProperties, for use in paint invalidation.

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

Index: third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp b/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp
index f57b66166d4eb51fe2e352176ad8449a072603d3..c00d8a442080932b5f5d2c66ca95cb658f79583d 100644
--- a/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp
@@ -486,6 +486,13 @@ void PaintPropertyTreeBuilder::buildTreeNodesForChildren(const LayoutObject& obj
     updatePerspective(object, context);
     updateSvgLocalToBorderBoxTransform(object, context);
     updateScrollTranslation(object, context);
+
+    if (object.objectPaintProperties()) {
+        std::unique_ptr<PropertyTreeState> contentsProperties =
+            wrapUnique(new PropertyTreeState(context.current.transform, context.current.clip, context.currentEffect));
+        object.getMutableForPainting().objectPaintProperties()->setContentsProperties(std::move(contentsProperties));
+    }
+
     updateOutOfFlowContext(object, context);
 }