Revert of Use a token to initialise ChannelMojo and MojoApplication everywhere.

content/child/mojo/mojo_application.h

Index: content/child/mojo/mojo_application.h
diff --git a/content/child/mojo/mojo_application.h b/content/child/mojo/mojo_application.h
index 68602c4fd36d892d966b4dc1a09031fdf6fbce58..34812120ba228069064fca6c2f417a9f7ea3241a 100644
--- a/content/child/mojo/mojo_application.h
+++ b/content/child/mojo/mojo_application.h
@@ -8,26 +8,44 @@
 #include <string>
 
 #include "base/macros.h"
+#include "content/common/mojo/channel_init.h"
 #include "content/common/mojo/service_registry_impl.h"
+#include "ipc/ipc_platform_file.h"
+#include "mojo/public/cpp/system/message_pipe.h"
+
+namespace base {
+class SequencedTaskRunner;
+}
+
+namespace IPC {
+class Message;
+}
 
 namespace content {
 
 // MojoApplication represents the code needed to setup a child process as a
-// Mojo application. Instantiate MojoApplication and call InitWithToken() with
-// a token passed from the process host. It makes the ServiceRegistry interface
-// available.
+// Mojo application via Chrome IPC. Instantiate MojoApplication and call its
+// OnMessageReceived method to give it a shot at handling Chrome IPC messages.
+// It makes the ServiceRegistry interface available.
 class MojoApplication {
  public:
-  MojoApplication();
+  explicit MojoApplication(
+      scoped_refptr<base::SequencedTaskRunner> io_task_runner);
   virtual ~MojoApplication();
 
-  // Initializes this MojoApplicaiton with a message pipe obtained using
-  // |token|.
-  void InitWithToken(const std::string& token);
+  // TODO(amistry): Remove OnMessageReceived() when all bootstrapping has
+  // migrated to these functions.
+  void InitWithToken(std::string token);
+
+  bool OnMessageReceived(const IPC::Message& msg);
 
   ServiceRegistry* service_registry() { return &service_registry_; }
 
  private:
+  void OnActivate(const IPC::PlatformFileForTransit& file);
+
+  scoped_refptr<base::SequencedTaskRunner> io_task_runner_;
+  ChannelInit channel_init_;
   ServiceRegistryImpl service_registry_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoApplication);