Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

ipc/mojo/scoped_ipc_support.cc

 // Copyright 2015 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 "ipc/mojo/scoped_ipc_support.h"
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/synchronization/condition_variable.h"
 #include "base/synchronization/lock.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/thread_task_runner_handle.h"
 #include "third_party/mojo/src/mojo/edk/embedder/embedder.h"
 #include "third_party/mojo/src/mojo/edk/embedder/process_delegate.h"
 
 namespace IPC {
 
 namespace {
-
+// TODO(use_chrome_edk)
+//class IPCSupportInitializer : public mojo::edk::ProcessDelegate {
 class IPCSupportInitializer : public mojo::embedder::ProcessDelegate {
  public:
   IPCSupportInitializer()
       : init_count_(0),
         shutting_down_(false),
         was_shut_down_(false),
         observer_(nullptr) {}
 
   ~IPCSupportInitializer() override { DCHECK(!observer_); }
 
@@ skipping 137 matching lines @@
 ScopedIPCSupport::ScopedIPCSupport(
     scoped_refptr<base::TaskRunner> io_thread_task_runner) {
   ipc_support_initializer.Get().Init(io_thread_task_runner);
 }
 
 ScopedIPCSupport::~ScopedIPCSupport() {
   ipc_support_initializer.Get().ShutDown();
 }
 
 }  // namespace IPC