Add IncrementWorkerRefCount() and DecrementWorkerRefCount() to RenderProcessHostImpl.

content/public/browser/render_process_host.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_
 
 #include "base/basictypes.h"
 #include "base/id_map.h"
 #include "base/process/kill.h"
@@ skipping 210 matching lines @@
   // devices (webcams, mics, etc) that were initially requested in the render
   // process associated with this RenderProcessHost.
   virtual void SetWebRtcLogMessageCallback(
       base::Callback<void(const std::string&)> callback) = 0;
 #endif
 
   // Tells the ResourceDispatcherHost to resume a deferred navigation without
   // transferring it to a new renderer process.
   virtual void ResumeDeferredNavigation(const GlobalRequestID& request_id) = 0;
 
+  // Called when the existance of the other renderer process which is connected
+  // to the SharedWorker in this renderer process has changed.
+  // It is only called when "enable-embedded-shared-worker" flag is set.
+  virtual void SetExternalClientStatus(bool has_external_worker_client) = 0;

[kinuko, 2014/03/04 04:48:48]

Does this need to be exposed at content/public?  The caller of this method will
be in content/ too, right?

Also a few comments:

The naming feels a bit vague to me while the comment gives very specific usage--
why it's called external client?

Also passing a single true/false boolean value seems to assume we have a single
caller for this method, while the method name is made somewhat generic.  Could
this be a pair of Add*/Remove* methods? (Then ServiceWorker could probably use
the same method)

[horo, 2014/03/04 06:40:43]

Changed to RenderProcessHostImpl::SetHasExternalWorkerClient(bool
has_external_worker_client).

This method is only called only from SharedWorkerServiceImpl which manages
SharedWorkers.
So I think SetHasExternalWorkerClient() is better than AddExternalWorker() and
RemoveExternalWorker().

[kinuko, 2014/03/04 06:58:46]

(As we talked offline) If this is specifically for SharedWorker can we name this
explicitly specific to SharedWorker? (E.g. SetHasRunningSharedWorker or
NotifySharedWorkerHasClients etc)  Otherwise I want to reuse this for
ServiceWorker too, and would it be in the Add/Remove format.

+
   // Static management functions -----------------------------------------------
 
   // Flag to run the renderer in process.  This is primarily
   // for debugging purposes.  When running "in process", the
   // browser maintains a single RenderProcessHost which communicates
   // to a RenderProcess which is instantiated in the same process
   // with the Browser.  All IPC between the Browser and the
   // Renderer is the same, it's just not crossing a process boundary.
 
   static bool run_renderer_in_process();
@@ skipping 41 matching lines @@
   // module.
   static size_t GetMaxRendererProcessCount();
 
   static void RegisterRendererMainThreadFactory(
       RendererMainThreadFactoryFunction create);
 };
 
 }  // namespace content.
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_