Adds a way to determine id of content handler that created app

mojo/application/public/cpp/application_connection.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 MOJO_APPLICATION_PUBLIC_CPP_APPLICATION_CONNECTION_H_
 #define MOJO_APPLICATION_PUBLIC_CPP_APPLICATION_CONNECTION_H_
 
 #include <string>
 
 #include "base/memory/weak_ptr.h"
@@ skipping 98 matching lines @@
 
   // Returns the local application's ServiceProvider interface. The return
   // value is owned by this connection.
   virtual ServiceProvider* GetLocalServiceProvider() = 0;
 
   // Register a handler to receive an error notification on the pipe to the
   // remote application's service provider.
   virtual void SetRemoteServiceProviderConnectionErrorHandler(
       const Closure& handler) = 0;
 
+  // Returns the id of the deepest content handler used in connecting to
+  // the application. If the content handler id has not yet been determined
+  // this returns false, use AddContentHandlerIDCallback() to schedule a
+  // callback when the content handler is has been obtained. A value of 0
+  // indicates no content handler was used in connecting to the application.
+  virtual bool GetContentHandlerID(uint32_t* content_handler_id) = 0;
+
+  // See description in GetTargetID(). If the id of the content handler has
+  // been obtained |callback| is run immediately.
+  virtual void AddContentHandlerIDCallback(const Closure& callback) = 0;
+
  protected:
   // Returns true if the connector was set, false if it was not set (e.g. by
   // some filtering policy preventing this interface from being exposed).
   virtual bool SetServiceConnectorForName(ServiceConnector* service_connector,
                                           const std::string& name) = 0;
 
   virtual base::WeakPtr<ApplicationConnection> GetWeakPtr() = 0;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_APPLICATION_PUBLIC_CPP_APPLICATION_CONNECTION_H_