Adds enableVirtualTime and setVirtualTimePolicy To Emulation domain.

third_party/WebKit/Source/core/fetch/FetchContext.h

Index: third_party/WebKit/Source/core/fetch/FetchContext.h
diff --git a/third_party/WebKit/Source/core/fetch/FetchContext.h b/third_party/WebKit/Source/core/fetch/FetchContext.h
index d4b54554edee8910f355e99a8c7ce3bf394d48e8..b27dcd24582e87e480a12d97e147f373460577f2 100644
--- a/third_party/WebKit/Source/core/fetch/FetchContext.h
+++ b/third_party/WebKit/Source/core/fetch/FetchContext.h
@@ -50,6 +50,7 @@ class ResourceResponse;
 class ResourceRequest;
 class ResourceTimingInfo;
 class WebTaskRunner;
+class WebViewScheduler;
 enum class WebCachePolicy;
 
 enum FetchResourceType {
@@ -113,6 +114,7 @@ public:
     virtual ResourceLoadPriority modifyPriorityForExperiments(ResourceLoadPriority priority) { return priority; }
 
     virtual WebTaskRunner* loadingTaskRunner() const { return nullptr; }
+    virtual WebViewScheduler* webViewScheduler() const { return nullptr; }

[dgozman, 2016/06/30 17:32:08]

I find it strange to have WebViewScheduler mentioned in FetchContenxt. Isn't
this a layering violation?

[alex clarke (OOO till 29th), 2016/07/01 14:09:14]

I think this is a good point and it seems it's not necessary to add this here. 
The FrameFetchContext looks a better place to tell the WebViewScheduler about
pending fetches.

 
 protected:
     FetchContext() { }