Provide a mechanism for the GCM driver to send message receipts to GCM.

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 21d30549d07030b043adfa405f0ab45eb6b94931..c28dd2d82d344fd22a34c7fec808497ff38612fc 100644
--- a/components/gcm_driver/gcm_driver.cc
+++ b/components/gcm_driver/gcm_driver.cc
@@ -13,6 +13,7 @@
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 #include "components/gcm_driver/gcm_app_handler.h"
+#include "components/gcm_driver/gcm_message_status.h"

[Peter Beverloo, 2017/02/08 17:09:09]

nit: this is already included in the header

[harkness, 2017/02/09 16:27:30]

Done.

 
 namespace gcm {
 
@@ -279,14 +280,17 @@ void GCMDriver::ClearCallbacks() {
 }
 
 void GCMDriver::DispatchMessage(const std::string& app_id,
-                                const IncomingMessage& message) {
+                                const IncomingMessage& message,
+                                const MessageReceiptCallback& callback) {
   encryption_provider_.DecryptMessage(
-      app_id, message, base::Bind(&GCMDriver::DispatchMessageInternal,
-                                  weak_ptr_factory_.GetWeakPtr(), app_id));
+      app_id, message,
+      base::Bind(&GCMDriver::DispatchMessageInternal,
+                 weak_ptr_factory_.GetWeakPtr(), app_id, callback));
 }
 
 void GCMDriver::DispatchMessageInternal(
     const std::string& app_id,
+    const MessageReceiptCallback& callback,
     GCMEncryptionProvider::DecryptionResult result,
     const IncomingMessage& message) {
   UMA_HISTOGRAM_ENUMERATION("GCM.Crypto.DecryptMessageResult", result,
@@ -295,6 +299,8 @@ void GCMDriver::DispatchMessageInternal(
   switch (result) {
     case GCMEncryptionProvider::DECRYPTION_RESULT_UNENCRYPTED:
     case GCMEncryptionProvider::DECRYPTION_RESULT_DECRYPTED:
+      // TODO(beverloo): When the DefaultAppHandler is gone, call
+      // SendMessageReceipt here if there isn't a valid app handler.
       GetAppHandler(app_id)->OnMessage(app_id, message);
       return;
     case GCMEncryptionProvider::DECRYPTION_RESULT_INVALID_ENCRYPTION_HEADER:
@@ -302,6 +308,7 @@ void GCMDriver::DispatchMessageInternal(
     case GCMEncryptionProvider::DECRYPTION_RESULT_NO_KEYS:
     case GCMEncryptionProvider::DECRYPTION_RESULT_INVALID_SHARED_SECRET:
     case GCMEncryptionProvider::DECRYPTION_RESULT_INVALID_PAYLOAD:
+      DoSendMessageReceipt(callback, GCMMessageStatus::GCM_ENCRYPTION_FAILURE);

[Peter Beverloo, 2017/02/08 17:09:09]

I'd argue that this should just be SendMessageReceipt() that lives on the UI
thread.

[harkness, 2017/02/09 16:27:30]

Now it just invokes the callback.

       RecordDecryptionFailure(app_id, result);
       return;
   }