Use token-based initialisation for the utility process MojoApplication.

content/browser/mojo/mojo_application_host.h

Index: content/browser/mojo/mojo_application_host.h
diff --git a/content/browser/mojo/mojo_application_host.h b/content/browser/mojo/mojo_application_host.h
index 0d7916fe9763f85464d3b392a11e7128dda38d37..7776d19dccf15a67fa0ef175394330accf656cef 100644
--- a/content/browser/mojo/mojo_application_host.h
+++ b/content/browser/mojo/mojo_application_host.h
@@ -6,6 +6,7 @@
 #define CONTENT_BROWSER_MOJO_MOJO_APPLICATION_HOST_H_
 
 #include <memory>
+#include <string>
 
 #include "base/macros.h"
 #include "base/process/process_handle.h"
@@ -42,6 +43,14 @@ class CONTENT_EXPORT MojoApplicationHost {
   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)