Enable use_once_callback for //content/common/*.mojom

content/browser/background_fetch/background_fetch_embedded_worker_test_helper.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_EMBEDDED_WORKER_TEST_HELPER_H_
 #define CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_EMBEDDED_WORKER_TEST_HELPER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 45 matching lines @@
   }
   const base::Optional<std::vector<BackgroundFetchSettledFetch>> last_fetches()
       const {
     return last_fetches_;
   }
 
  protected:
   // EmbeddedWorkerTestHelper overrides:
   void OnBackgroundFetchAbortEvent(
       const std::string& tag,
-      const mojom::ServiceWorkerEventDispatcher::
-          DispatchBackgroundFetchAbortEventCallback& callback) override;
+      mojom::ServiceWorkerEventDispatcher::
+          DispatchBackgroundFetchAbortEventCallback callback) override;
   void OnBackgroundFetchClickEvent(
       const std::string& tag,
       mojom::BackgroundFetchState state,
-      const mojom::ServiceWorkerEventDispatcher::
-          DispatchBackgroundFetchClickEventCallback& callback) override;
+      mojom::ServiceWorkerEventDispatcher::
+          DispatchBackgroundFetchClickEventCallback callback) override;
   void OnBackgroundFetchFailEvent(
       const std::string& tag,
       const std::vector<BackgroundFetchSettledFetch>& fetches,
-      const mojom::ServiceWorkerEventDispatcher::
-          DispatchBackgroundFetchFailEventCallback& callback) override;
+      mojom::ServiceWorkerEventDispatcher::
+          DispatchBackgroundFetchFailEventCallback callback) override;
   void OnBackgroundFetchedEvent(
       const std::string& tag,
       const std::vector<BackgroundFetchSettledFetch>& fetches,
-      const mojom::ServiceWorkerEventDispatcher::
-          DispatchBackgroundFetchedEventCallback& callback) override;
+      mojom::ServiceWorkerEventDispatcher::
+          DispatchBackgroundFetchedEventCallback callback) override;
 
  private:
   bool fail_abort_event_ = false;
   bool fail_click_event_ = false;
   bool fail_fetch_fail_event_ = false;
   bool fail_fetched_event_ = false;
 
   base::Closure abort_event_closure_;
   base::Closure click_event_closure_;
   base::Closure fetch_fail_event_closure_;
   base::Closure fetched_event_closure_;
 
   base::Optional<std::string> last_tag_;
   base::Optional<mojom::BackgroundFetchState> last_state_;
   base::Optional<std::vector<BackgroundFetchSettledFetch>> last_fetches_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundFetchEmbeddedWorkerTestHelper);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_EMBEDDED_WORKER_TEST_HELPER_H_