Notify GCMAppHandlers when the store is reset, so they clear cached IDs

chrome/browser/extensions/extension_gcm_app_handler.cc

Index: chrome/browser/extensions/extension_gcm_app_handler.cc
diff --git a/chrome/browser/extensions/extension_gcm_app_handler.cc b/chrome/browser/extensions/extension_gcm_app_handler.cc
index 4a7cc24bff70f0866dce8d85c4af45cb6455435b..00f30d03d80f096b4e8d5d2189741273505286b6 100644
--- a/chrome/browser/extensions/extension_gcm_app_handler.cc
+++ b/chrome/browser/extensions/extension_gcm_app_handler.cc
@@ -68,6 +68,11 @@ void ExtensionGCMAppHandler::ShutdownHandler() {
   js_event_router_.reset();
 }
 
+void ExtensionGCMAppHandler::OnStoreReset() {
+  // TODO(johnme): Notify the extension somehow that its registration was
+  // invalidated and deleted?
+}
+
 void ExtensionGCMAppHandler::OnMessage(const std::string& app_id,
                                        const gcm::IncomingMessage& message) {
   js_event_router_->OnMessage(app_id, message);