Add IncrementWorkerRefCount() and DecrementWorkerRefCount() to RenderProcessHostImpl.

content/browser/renderer_host/render_process_host_impl.h

Index: content/browser/renderer_host/render_process_host_impl.h
diff --git a/content/browser/renderer_host/render_process_host_impl.h b/content/browser/renderer_host/render_process_host_impl.h
index d2fbe9a5599def233956b3e7a109e8ed8db016d1..e42eb30b8b48633eaef4d2b40176b2d8be930118 100644
--- a/content/browser/renderer_host/render_process_host_impl.h
+++ b/content/browser/renderer_host/render_process_host_impl.h
@@ -226,6 +226,12 @@ class CONTENT_EXPORT RenderProcessHostImpl
     is_guest_ = is_guest;
   }
 
+  // Called when the existence of the other renderer process which is connected
+  // to the Worker in this renderer process has changed.
+  // It is only called when "enable-embedded-shared-worker" flag is set.
+  void IncrementWorkerRefCount();
+  void DecrementWorkerRefCount();
+
  protected:
   // A proxy for our IPC::Channel that lives on the IO thread (see
   // browser_process.h)
@@ -415,6 +421,8 @@ class CONTENT_EXPORT RenderProcessHostImpl
   // Message filter and dispatcher for screen orientation.
   ScreenOrientationDispatcherHost* screen_orientation_dispatcher_host_;
 
+  int worker_ref_count_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderProcessHostImpl);
 };