Support interpolation of animatable shorthand properties containing var()

third_party/WebKit/Source/core/animation/CSSInterpolationType.h

Index: third_party/WebKit/Source/core/animation/CSSInterpolationType.h
diff --git a/third_party/WebKit/Source/core/animation/CSSInterpolationType.h b/third_party/WebKit/Source/core/animation/CSSInterpolationType.h
index 6edfcb57269ab68f66c178bf1ae00a069e0f2f2e..4b39d33576aaef111be2ac139b4e1c764f3a55a8 100644
--- a/third_party/WebKit/Source/core/animation/CSSInterpolationType.h
+++ b/third_party/WebKit/Source/core/animation/CSSInterpolationType.h
@@ -7,15 +7,12 @@
 
 #include "core/animation/InterpolationEnvironment.h"
 #include "core/animation/InterpolationType.h"
-#include "core/css/CSSPropertyMetadata.h"
 
 namespace blink {
 
 class CSSInterpolationType : public InterpolationType {
 protected:
-    CSSInterpolationType(CSSPropertyID property)
-        : InterpolationType(PropertyHandle(property))
-    { }
+    CSSInterpolationType(CSSPropertyID);
 
     CSSPropertyID cssProperty() const { return getProperty().cssProperty(); }