Integrate InstanceID with GCM crypto provider

components/gcm_driver/gcm_driver.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 COMPONENTS_GCM_DRIVER_GCM_DRIVER_H_
 #define COMPONENTS_GCM_DRIVER_GCM_DRIVER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 120 matching lines @@
   // |receiver_id|: registration ID of the receiver party.
   // |message|: message to be sent.
   // |callback|: to be called once the asynchronous operation is done.
   void Send(const std::string& app_id,
             const std::string& receiver_id,
             const OutgoingMessage& message,
             const SendCallback& callback);
 
   // Get the public encryption key and the authentication secret associated with
   // |app_id|. If none have been associated with |app_id| yet, they will be
-  // created. The |callback| will be invoked when it is available.
+  // created. The |callback| will be invoked when it is available. Only use with
+  // GCM registrations; use InstanceID::GetEncryptionInfo for InstanceID tokens.
   void GetEncryptionInfo(const std::string& app_id,
                          const GetEncryptionInfoCallback& callback);
 
   const GCMAppHandlerMap& app_handlers() const { return app_handlers_; }
 
   // This method must be called before destroying the GCMDriver. Once it has
   // been called, no other GCMDriver methods may be used.
   virtual void Shutdown();
 
   // Called when the user signs in to or out of a GAIA account.
@@ skipping 78 matching lines @@
   //
   // |scope| is used to identify the component that requests a custom interval
   // to be set, and allows that component to later revoke the setting.
   // |interval_ms| should be between 2 minues and 15 minues (28 minues on
   // cellular networks). For details check
   // GetMin/MaxClientHeartbeatItnervalMs() in HeartbeatManager.
   virtual void AddHeartbeatInterval(const std::string& scope,
                                     int interval_ms) = 0;
   virtual void RemoveHeartbeatInterval(const std::string& scope) = 0;
 
+  // Should only be used by the InstanceID system.
+  GCMEncryptionProvider* encryption_provider_internal() {

[Peter Beverloo, 2016/05/11 16:04:59]

(1) Please move this after GetInstanceIDHandlerInternal() to group them
together.
(2) Please rename this to GetEncryptionProviderInternal() for consistency. As
such, also move to .cc.
(3) Have a brief half-sentence describing *what* it is.

[johnme, 2016/05/13 16:25:45]

Done.

+    return &encryption_provider_;
+  }
+
  protected:
   // Ensures that the GCM service starts (if necessary conditions are met).
   virtual GCMClient::Result EnsureStarted(GCMClient::StartMode start_mode) = 0;
 
   // Platform-specific implementation of Register.
   virtual void RegisterImpl(const std::string& app_id,
                             const std::vector<std::string>& sender_ids) = 0;
 
   // Platform-specific implementation of Unregister.
   virtual void UnregisterImpl(const std::string& app_id) = 0;
@@ skipping 84 matching lines @@
   DefaultGCMAppHandler default_app_handler_;
 
   base::WeakPtrFactory<GCMDriver> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GCMDriver);
 };
 
 }  // namespace gcm
 
 #endif  // COMPONENTS_GCM_DRIVER_GCM_DRIVER_H_