[SPv2] Respect transform-style in the Blink and cc property trees.

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

Index: third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.h
diff --git a/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.h b/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.h
index 16f07086d7c79ffe1a76b6eefae797928862a7c9..2fd33a0340ad7ae69e7efba09626971b56e901c6 100644
--- a/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.h
+++ b/third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.h
@@ -29,6 +29,14 @@ struct PaintPropertyTreeBuilderContext {
         // the space with its own layout location.
         TransformPaintPropertyNode* transform = nullptr;
         LayoutPoint paintOffset;
+        // Whether newly created children should flatten their inherited transform
+        // (equivalently, draw into the plane of their parent). Should generally
+        // be updated whenever |transform| is; flattening only needs to happen
+        // to immediate children.
+        bool shouldFlattenInheritedTransform = false;
+        // Rendering context for 3D sorting. See
+        // TransformPaintPropertyNode::renderingContextID.
+        unsigned renderingContextID = 0;
         // The clip node describes the accumulated raster clip for the current subtree.
         // Note that the computed raster region in canvas space for a clip node is independent from
         // the transform and paint offset above. Also the actual raster region may be affected