Changing animate to beginFrame and use struct rather than naked double to allow extension.

public/platform/WebFrameTime.h

Index: public/platform/WebFrameTime.h
diff --git a/public/platform/WebWaitableEvent.h b/public/platform/WebFrameTime.h
similarity index 58%
copy from public/platform/WebWaitableEvent.h
copy to public/platform/WebFrameTime.h
index f1b59f0a263afe5afd887863e98d52d9cfa3e95e..1050291c23f3db6177e84cc5bb3a7aa9feec7b15 100644
--- a/public/platform/WebWaitableEvent.h
+++ b/public/platform/WebFrameTime.h
@@ -28,28 +28,42 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef WebWaitableEvent_h
-#define WebWaitableEvent_h
+#ifndef WebFrameTime_h
+#define WebFrameTime_h
 
 #include "WebCommon.h"
 
 namespace blink {
 
-// Provides a thread synchronization that can be used to allow one thread to
-// wait until another thread to finish some work.
-class WebWaitableEvent {
-public:
-    virtual ~WebWaitableEvent() { }
+struct WebFrameTime {

[Sami, 2014/07/02 13:24:38]

Any reason not just to call this WebBeginFrameArgs and pass in the same data as
we get through BeginFrame? Right now this is almost exactly the same except we
have just one predicted frame time instead of an interval.

To be clear I'm not opposed to calling this WebFrameTime, but let's make it
compatible with BeginFrameArgs.

+    WebFrameTime(double lastFrameTime, double renderDeadline, double displayFrameTime, double predictedNextDisplayFrameTime)
+        : lastFrameTime(lastFrameTime)
+        , renderDeadline(renderDeadline)
+        , displayFrameTime(displayFrameTime)
+        , predictedNextDisplayFrameTime(predictedNextDisplayFrameTime)
+    { }
 
-    // Waits indefinitely for the event to be signaled.
-    virtual void wait() = 0;
+    // FIXME(mithro): Upgrade the time in CLOCK_MONOTONIC values to use a
+    // TimeTick like class rather than a bare double.
 
-    // Puts the event in the signaled state. Causing any thread blocked on Wait
-    // to be woken up. The event state is reset to non-signaled after
-    // a waiting thread has been released.
-    virtual void signal() = 0;
+    // Time in CLOCK_MONOTONIC that is the most recent vsync time.
+    double lastFrameTime;
+
+    // Time in CLOCK_MONOTONIC by which rendering must be finished by to not
+    // stall the pipeline.
+    double renderDeadline;
+
+    // Time in CLOCK_MONOTONIC that the frame will hit the glass of the display
+    // if rendered within the deadline. This time may be identical to
+    // lastFrameTime.
+    double displayFrameTime;
+
+    // Time in CLOCK_MONOTONIC that is the predicated next value for
+    // displayFrameTime. The next displayFrameTime should be this value or
+    // greater.
+    double predictedNextDisplayFrameTime;
 };
 
 } // namespace blink
 
-#endif // WebWaitableEvent_h
+#endif