Bug 998246 part 4 - Add currentTime member to AnimationTimeline; r=bz

dom/animation/AnimationTimeline.cpp

@@ -6,6 +6,10 @@
 #include "AnimationTimeline.h"
 #include "mozilla/dom/AnimationTimelineBinding.h"
 #include "nsContentUtils.h"
+#include "nsIPresShell.h"
+#include "nsPresContext.h"
+#include "nsRefreshDriver.h"
+#include "nsDOMNavigationTiming.h"
 
 namespace mozilla {
 namespace dom {
@@ -21,5 +25,28 @@ AnimationTimeline::WrapObject(JSContext* aCx)
   return AnimationTimelineBinding::Wrap(aCx, this);
 }
 
+Nullable<double>
+AnimationTimeline::GetCurrentTime() const
+{
+  Nullable<double> result; // Default ctor initializes to null
+
+  nsIPresShell* presShell = mDocument->GetShell();
+  if (!presShell)
+    return result;
+
+  nsPresContext* presContext = presShell->GetPresContext();
+  if (!presContext)
+    return result;
+
+  nsRefPtr<nsDOMNavigationTiming> timing = mDocument->GetNavigationTiming();
+  if (!timing)
+    return result;
+
+  TimeStamp now = presContext->RefreshDriver()->MostRecentRefresh();
+  result.SetValue(timing->TimeStampToDOMHighRes(now));
+
+  return result;
+}
+
 } // namespace dom
 } // namespace mozilla

dom/animation/AnimationTimeline.h

@@ -34,6 +34,8 @@ public:
   nsISupports* GetParentObject() const { return mDocument; }
   virtual JSObject* WrapObject(JSContext* aCx) MOZ_OVERRIDE;
 
+  Nullable<double> GetCurrentTime() const;
+
 protected:
   nsCOMPtr<nsIDocument> mDocument;
 };

dom/webidl/AnimationTimeline.webidl

@@ -12,7 +12,7 @@
 
 [Pref="dom.animations-api.core.enabled"]
 interface AnimationTimeline {
-  // readonly attribute double? currentTime;
+  readonly attribute double? currentTime;
   // AnimationPlayer            play (optional TimedItem? source = null);
   // sequence<AnimationPlayer>  getAnimationPlayers ();
 };