Push API: use (un)subscription instead of (un)registration

content/renderer/push_messaging/push_messaging_dispatcher.h

Index: content/renderer/push_messaging/push_messaging_dispatcher.h
diff --git a/content/renderer/push_messaging/push_messaging_dispatcher.h b/content/renderer/push_messaging/push_messaging_dispatcher.h
index 56eaa852820d80f6cf86ea18dc609a4a8ff9607b..77da6b6273264cbe6281c83156a485da9390c26e 100644
--- a/content/renderer/push_messaging/push_messaging_dispatcher.h
+++ b/content/renderer/push_messaging/push_messaging_dispatcher.h
@@ -50,11 +50,11 @@ class PushMessagingDispatcher : public RenderFrameObserver,
       blink::WebPushSubscriptionCallbacks* callbacks,
       const Manifest& manifest);
 
-  void OnRegisterFromDocumentSuccess(int32_t request_id,
+  void OnSubscribeFromDocumentSuccess(int32_t request_id,
                                      const GURL& endpoint,
                                      const std::string& registration_id);
 
-  void OnRegisterFromDocumentError(int32_t request_id,
+  void OnSubscribeFromDocumentError(int32_t request_id,
                                    PushRegistrationStatus status);
 
   IDMap<blink::WebPushSubscriptionCallbacks, IDMapOwnPointer>