List message decryption failures on chrome://gcm-internals

components/gcm_driver/fake_gcm_driver.h

Index: components/gcm_driver/fake_gcm_driver.h
diff --git a/components/gcm_driver/fake_gcm_driver.h b/components/gcm_driver/fake_gcm_driver.h
index 6d92dab2be23a9bce45b0ce3f96eb4cab6137c0c..d7c63fbd313607791900d5831f8c5e9cfb43c1f1 100644
--- a/components/gcm_driver/fake_gcm_driver.h
+++ b/components/gcm_driver/fake_gcm_driver.h
@@ -54,6 +54,9 @@ class FakeGCMDriver : public GCMDriver {
   void SendImpl(const std::string& app_id,
                 const std::string& receiver_id,
                 const OutgoingMessage& message) override;
+  void RecordDecryptionFailure(const std::string& app_id,
+                               GCMEncryptionProvider::DecryptionFailure reason)
+      override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FakeGCMDriver);