Use token-based initialisation for the utility process MojoApplication.

content/browser/mojo/mojo_application_host.h

 // Copyright 2014 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_BROWSER_MOJO_MOJO_APPLICATION_HOST_H_
 #define CONTENT_BROWSER_MOJO_MOJO_APPLICATION_HOST_H_
 
 #include <memory>
+#include <string>
 
 #include "base/macros.h"
 #include "base/process/process_handle.h"
 #include "build/build_config.h"
 #include "content/common/application_setup.mojom.h"
 #include "content/common/mojo/channel_init.h"
 #include "content/common/mojo/service_registry_impl.h"
 #include "mojo/edk/embedder/scoped_platform_handle.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 
@@ skipping 16 matching lines @@
  public:
   MojoApplicationHost();
   ~MojoApplicationHost();
 
   // Two-phase initialization:
   //  1- Init makes service_registry() available synchronously.
   //  2- Activate establishes the actual connection to the peer process.
   bool Init();
   void Activate(IPC::Sender* sender, base::ProcessHandle process_handle);
 
+  // Use a shared token to initialize the application. Returns a token to pass
+  // to the child process.
+  std::string InitWithToken();
+
+  // Use a message pipe to initialize the application. Used for in-process child
+  // threads.
+  mojo::ScopedMessagePipeHandle InitWithPipe();

[Ken Rockot(use gerrit already), 2016/04/11 15:04:18]

Did you try simply using the token for the in-process case as well? It should
work because of this code:
https://code.google.com/p/chromium/codesearch#chromium/src/mojo/edk/system/no...

[Anand Mistry (off Chromium), 2016/04/12 00:31:14]

I did separate approaches after chatting with Sam who ran into ordering issues.
I tried using just token init and it seems to work (ran test 1000 times, no
failures). So I've changed to just using token init.

+
   ServiceRegistry* service_registry() { return &service_registry_; }
 
 #if defined(OS_ANDROID)
   ServiceRegistryAndroid* service_registry_android() {
     return service_registry_android_.get();
   }
 #endif
 
   void OverrideIOTaskRunnerForTest(
       scoped_refptr<base::TaskRunner> io_task_runner);
@@ skipping 12 matching lines @@
 #if defined(OS_ANDROID)
   std::unique_ptr<ServiceRegistryAndroid> service_registry_android_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(MojoApplicationHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MOJO_MOJO_APPLICATION_HOST_H_