Let IPC::SyncMessageFilter take advantage of thread-safe Send.

content/child/child_thread_impl.cc

 // 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.
 
 #include "content/child/child_thread_impl.h"
 
 #include <signal.h>
 
 #include <string>
 
@@ skipping 348 matching lines @@
   if (!IsInBrowserProcess())
     IPC::Logging::GetInstance()->SetIPCSender(this);
 #endif
 
 #if defined(OS_WIN)
   attachment_broker_.reset(new IPC::AttachmentBrokerUnprivilegedWin());
 #endif
 
   mojo_application_.reset(new MojoApplication(GetIOTaskRunner()));
 
-  sync_message_filter_ =
-      new IPC::SyncMessageFilter(ChildProcess::current()->GetShutDownEvent());
+  histogram_message_filter_ = new ChildHistogramMessageFilter();

[jam, 2015/08/04 23:06:41]

why move this code?

[Ken Rockot(use gerrit already), 2015/08/04 23:55:44]

only to preserve the order of the filters. reverted since this doesn't matter

+  channel_->AddFilter(histogram_message_filter_.get());
+
+  sync_message_filter_ = channel_->AddNewSyncMessageFilter();
+
   thread_safe_sender_ = new ThreadSafeSender(
       message_loop_->task_runner(), sync_message_filter_.get());
 
   resource_dispatcher_.reset(new ResourceDispatcher(
       this, message_loop()->task_runner()));
   websocket_dispatcher_.reset(new WebSocketDispatcher);
   file_system_dispatcher_.reset(new FileSystemDispatcher());
 
-  histogram_message_filter_ = new ChildHistogramMessageFilter();
   resource_message_filter_ =
       new ChildResourceMessageFilter(resource_dispatcher());
 
   service_worker_message_filter_ =
       new ServiceWorkerMessageFilter(thread_safe_sender_.get());
 
   quota_message_filter_ =
       new QuotaMessageFilter(thread_safe_sender_.get());
   quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(),
                                               quota_message_filter_.get()));
   geofencing_message_filter_ =
       new GeofencingMessageFilter(thread_safe_sender_.get());
   notification_dispatcher_ =
       new NotificationDispatcher(thread_safe_sender_.get());
   push_dispatcher_ = new PushDispatcher(thread_safe_sender_.get());
 
-  channel_->AddFilter(histogram_message_filter_.get());
-  channel_->AddFilter(sync_message_filter_.get());
   channel_->AddFilter(resource_message_filter_.get());
   channel_->AddFilter(quota_message_filter_->GetFilter());
   channel_->AddFilter(notification_dispatcher_->GetFilter());
   channel_->AddFilter(push_dispatcher_->GetFilter());
   channel_->AddFilter(service_worker_message_filter_->GetFilter());
   channel_->AddFilter(geofencing_message_filter_->GetFilter());
 
   if (!IsInBrowserProcess()) {
     // In single process mode, browser-side tracing will cover the whole
     // process including renderers.
@@ skipping 301 matching lines @@
 
 void ChildThreadImpl::OnProcessBackgrounded(bool background) {
   // Set timer slack to maximum on main thread when in background.
   base::TimerSlack timer_slack = base::TIMER_SLACK_NONE;
   if (background)
     timer_slack = base::TIMER_SLACK_MAXIMUM;
   base::MessageLoop::current()->SetTimerSlack(timer_slack);
 }
 
 }  // namespace content