Make the web-animations engine use the passed in blink::WebFrameTime values.

Source/core/animation/DocumentAnimations.h

Index: Source/core/animation/DocumentAnimations.h
diff --git a/Source/core/animation/DocumentAnimations.h b/Source/core/animation/DocumentAnimations.h
index f92f9942b497f88054d36bb205ed4f9ac7b9dc95..1c3dd0a6333c0cf6684fb8bcdb2198e15905c2b6 100644
--- a/Source/core/animation/DocumentAnimations.h
+++ b/Source/core/animation/DocumentAnimations.h
@@ -32,6 +32,7 @@
 #define DocumentAnimations_h
 
 #include "core/CSSPropertyNames.h"
+#include "public/platform/WebFrameTime.h"
 
 namespace WebCore {
 
@@ -41,7 +42,7 @@ class Node;
 
 class DocumentAnimations {
 public:
-    static void updateAnimationTimingForAnimationFrame(Document&, double monotonicAnimationStartTime);
+    static void updateAnimationTimingForAnimationFrame(Document&, blink::WebFrameTime monotonicAnimationStartTime);
     static bool needsOutdatedAnimationPlayerUpdate(const Document&);
     static void updateOutdatedAnimationPlayersIfNeeded(Document&);
     static void updateAnimationTimingForGetComputedStyle(Node&, CSSPropertyID);