Teach the GCM Driver how to decrypt incoming messages.

components/gcm_driver/gcm_driver.cc

Index: components/gcm_driver/gcm_driver.cc
diff --git a/components/gcm_driver/gcm_driver.cc b/components/gcm_driver/gcm_driver.cc
index 16e04afde7b45a97c9a7bdd4938ada07a2d90be2..46381b30d59e1e07e4903514b7103a8c62a4050b 100644
--- a/components/gcm_driver/gcm_driver.cc
+++ b/components/gcm_driver/gcm_driver.cc
@@ -256,6 +256,30 @@ bool GCMDriver::HasRegisterCallback(const std::string& app_id) {
   return register_callbacks_.find(app_id) != register_callbacks_.end();
 }
 
+void GCMDriver::DispatchMessage(const std::string& app_id,
+                                const IncomingMessage& message) {
+  if (!encryption_provider_.IsEncryptedMessage(message)) {
+    GetAppHandler(app_id)->OnMessage(app_id, message);
+    return;
+  }
+
+  encryption_provider_.DecryptMessage(
+      app_id, message, base::Bind(&GCMDriver::DispatchDecryptedMessage,
+                                  weak_ptr_factory_.GetWeakPtr(), app_id));
+}
+
+void GCMDriver::DispatchDecryptedMessage(const std::string& app_id,
+                                         const IncomingMessage& message,
+                                         bool decryption_successful) {
+  if (!decryption_successful) {
+    // TODO(peter): Introduce a new event on app handlers for this scenario.
+    LOG(ERROR) << "Unable to decrypt message for " << app_id;
+    return;
+  }
+
+  GetAppHandler(app_id)->OnMessage(app_id, message);
+}
+
 void GCMDriver::ClearCallbacks() {
   register_callbacks_.clear();
   unregister_callbacks_.clear();