Add ChildMessageFilter, a base class for renderer/worker cross-thread MessageFilter

content/child/service_worker/service_worker_message_filter.cc

Index: content/child/service_worker/service_worker_message_filter.cc
diff --git a/content/child/service_worker/service_worker_message_filter.cc b/content/child/service_worker/service_worker_message_filter.cc
index aaacabec04c89e606dd04d7dc946e6cbee5e9e1f..68e6be3fecf4278a98e10e568dcc813659a33b3c 100644
--- a/content/child/service_worker/service_worker_message_filter.cc
+++ b/content/child/service_worker/service_worker_message_filter.cc
@@ -4,15 +4,11 @@
 
 #include "content/child/service_worker/service_worker_message_filter.h"
 
-#include "ipc/ipc_message_macros.h"
-#include "base/bind.h"
 #include "base/message_loop/message_loop_proxy.h"
-#include "base/pickle.h"
 #include "content/child/service_worker/service_worker_dispatcher.h"
 #include "content/child/thread_safe_sender.h"
-#include "webkit/child/worker_task_runner.h"
-
-using webkit_glue::WorkerTaskRunner;
+#include "content/child/worker_thread_task_runner.h"
+#include "ipc/ipc_message_macros.h"
 
 namespace content {
 
@@ -22,25 +18,24 @@ ServiceWorkerMessageFilter::ServiceWorkerMessageFilter(ThreadSafeSender* sender)
 
 ServiceWorkerMessageFilter::~ServiceWorkerMessageFilter() {}
 
-bool ServiceWorkerMessageFilter::OnMessageReceived(const IPC::Message& msg) {
+base::TaskRunner* ServiceWorkerMessageFilter::OverrideTaskRunnerForMessage(
+    const IPC::Message& msg) {
   if (IPC_MESSAGE_CLASS(msg) != ServiceWorkerMsgStart)
-    return false;
-  int thread_id = 0;
-  bool result = PickleIterator(msg).ReadInt(&thread_id);
-  DCHECK(result);
-  base::Closure closure =
-      base::Bind(&ServiceWorkerMessageFilter::DispatchMessage, this, msg);
-  if (!thread_id) {
-    main_thread_loop_proxy_->PostTask(FROM_HERE, closure);
-    return true;
-  }
-  WorkerTaskRunner::Instance()->PostTask(thread_id, closure);
-  return true;
+    return NULL;
+  int ipc_thread_id = 0;
+  const bool success = PickleIterator(msg).ReadInt(&ipc_thread_id);
+  DCHECK(success);
+  if (!ipc_thread_id)
+    return main_thread_loop_proxy_.get();
+  return new WorkerThreadTaskRunner(ipc_thread_id);
 }
 
-void ServiceWorkerMessageFilter::DispatchMessage(const IPC::Message& msg) {
+bool ServiceWorkerMessageFilter::OnMessageReceived(const IPC::Message& msg) {
+  if (IPC_MESSAGE_CLASS(msg) != ServiceWorkerMsgStart)
+    return false;
   ServiceWorkerDispatcher::ThreadSpecificInstance(thread_safe_sender_.get())
       ->OnMessageReceived(msg);
+  return false;
 }
 
 }  // namespace content