Add blink::ServiceRegistry and expose it from LocalFrame and Platform.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 0b2b95ec19c8fff88f0c6c20be0eac8c18e09fb3..bb7b4e74ef3b6964f37d02d9e96a6dd2973988ef 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -1196,8 +1196,9 @@ void RenderThreadImpl::InitializeWebKit(
 
   SetRuntimeFeaturesDefaultsAndUpdateFromArgs(command_line);
 
-  blink_platform_impl_.reset(
-      new RendererBlinkPlatformImpl(renderer_scheduler_.get()));
+  blink_platform_impl_.reset(new RendererBlinkPlatformImpl(
+      renderer_scheduler_.get(),
+      static_cast<ServiceRegistryImpl*>(service_registry())->GetWeakPtr()));
   blink::initialize(blink_platform_impl_.get());
 
   v8::Isolate* isolate = blink::mainThreadIsolate();