Adds a flag to support "Virtual Time" to the blink scheduler

content/renderer/renderer_blink_platform_impl.h

Index: content/renderer/renderer_blink_platform_impl.h
diff --git a/content/renderer/renderer_blink_platform_impl.h b/content/renderer/renderer_blink_platform_impl.h
index 235a66fdaabdfa11aa965b4185a9903205ba21c7..39c273f24130898ee394932a2af9ae70cbbe090b 100644
--- a/content/renderer/renderer_blink_platform_impl.h
+++ b/content/renderer/renderer_blink_platform_impl.h
@@ -171,6 +171,9 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
                     const blink::WebString& sample) override;
   void recordRapporURL(const char* metric, const blink::WebURL& url) override;
 
+  double currentTime() override;

[Sami, 2015/10/28 20:00:35]

Should we leave these two out of this patch until we figure out how to handle
the global virtual time => per page virtual time mapping?

[alex clarke (OOO till 29th), 2015/10/29 18:07:30]

We aren't planning on supporting multiple pages yet, and we have to do this
anyway.  Why not do it now?

Down the line this is wired up in a way that will let us perform the mapping
correctly (either RendererSchedulerImpl, or a class it delegates the logic to,
will be able to do the mapping).

+  double monotonicallyIncreasingTime() override;
+
   // Set the PlatformEventObserverBase in |platform_event_observers_| associated
   // with |type| to |observer|. If there was already an observer associated to
   // the given |type|, it will be replaced.
@@ -275,6 +278,8 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
 
   IDMap<PlatformEventObserverBase, IDMapOwnPointer> platform_event_observers_;
 
+  scheduler::RendererScheduler* renderer_scheduler_;  // NOT OWNED
+
   DISALLOW_COPY_AND_ASSIGN(RendererBlinkPlatformImpl);
 };