PPB_HostResolver_Private is switched to the new Pepper proxy.

content/public/browser/browser_ppapi_host.h

Index: content/public/browser/browser_ppapi_host.h
diff --git a/content/public/browser/browser_ppapi_host.h b/content/public/browser/browser_ppapi_host.h
index 08c5f074af2be597174809b09f6525b353b8ceda..8e7a208490f5ce5b4cbd5fff43130df5ff32b1f2 100644
--- a/content/public/browser/browser_ppapi_host.h
+++ b/content/public/browser/browser_ppapi_host.h
@@ -9,6 +9,7 @@
 #include "base/process.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "googleurl/src/gurl.h"
 #include "ppapi/c/pp_instance.h"
@@ -83,6 +84,58 @@ class CONTENT_EXPORT BrowserPpapiHost {
   // Get the Document/Plugin URLs for the given PP_Instance.
   virtual GURL GetDocumentURLForInstance(PP_Instance instance) = 0;
   virtual GURL GetPluginURLForInstance(PP_Instance instance) = 0;
+
+
+  // Schedules the given callback to execute on the UI thread of the browser,
+  // passing the RenderProcess associated with the given instance as a
+  // parameter.
+  //
+  // Normally this would be called from a ResourceHost with the reply using
+  // a weak pointer to itself.
+  //
+  // Importantly, the task will not be run if the RenderView is destroyed by
+  // the time we get to the UI thread, or if the PP_Instance is invalid, but
+  // the reply will still be run. The return type in this case will be a
+  // defaultconstructed |ReturnType|.
+  //
+  // So you may want to make sure you don't do silly things in the reply
+  // handler if the task on the UI thread is never run and you get a
+  // defaultconstructed result.
+  template<typename ReturnType>
+  bool PostOnUIThreadWithRenderProcessAndReply(

[yzshen1, 2012/12/20 20:00:20]

Is it possible to be done using ResourceMessageFilter?

+      const tracked_objects::Location& from_here,
+      PP_Instance instance,
+      const base::Callback<ReturnType(RenderProcessHost*)>& task,
+      const base::Callback<void(ReturnType)>& reply) const {
+    int render_process_id, render_view_id;
+    bool success = GetRenderViewIDsForInstance(instance,
+                                               &render_process_id,
+                                               &render_view_id);
+    if (!success)
+      return false;
+    BrowserThread::PostTaskAndReplyWithResult(
+        BrowserThread::UI,
+        from_here,
+        base::Bind(&CallWithRenderProcessHost<ReturnType>,
+                   render_process_id, task),
+        reply);
+    return true;
+  }
+
+ protected:
+  // Backend for PostOnUIThreadWithRenderViewAndReply. This converts the IDs
+  // to a RenderProcessHost and calls the function, or returns a
+  // defaultconstructed return value on error.
+  template<typename ReturnType>
+  static ReturnType CallWithRenderProcessHost(
+      int render_process_id,
+      const base::Callback<ReturnType(RenderProcessHost*)>& task) {
+    RenderProcessHost* render_process_host =
+        RenderProcessHost::FromID(render_process_id);
+    if (render_process_host)
+      return task.Run(render_process_host);
+    return ReturnType();
+  }
 };
 
 }  // namespace content