CSS will-change: Mentioning transform properties gives containing block

third_party/WebKit/Source/core/style/ComputedStyle.cpp

Index: third_party/WebKit/Source/core/style/ComputedStyle.cpp
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.cpp b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
index 2fc9f7e27dc9240c7390ee3a11a628a2d71227d6..463710e6a4a73ed72c744a8ea425d80bbdcc5a4c 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.cpp
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
@@ -1230,6 +1230,10 @@ bool ComputedStyle::hasWillChangeTransformHint() const {
     switch (property) {
       case CSSPropertyTransform:
       case CSSPropertyAliasWebkitTransform:
+      case CSSPropertyPerspective:
+      case CSSPropertyTranslate:
+      case CSSPropertyScale:
+      case CSSPropertyRotate:
         return true;
       default:
         break;