[Offline Pages] Fix official build failure (using clang) caused by unused variables.

chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h

Index: chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h
diff --git a/chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h b/chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h
index c3297175fa9b6c1de8de949ddcc486a669c73600..4f4b9a8a8e6286a5093a159fe95f6888d1e549f5 100644
--- a/chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h
+++ b/chrome/browser/android/offline_pages/evaluation/offline_page_evaluation_bridge.h
@@ -30,6 +30,8 @@ class OfflinePageEvaluationBridge : public OfflinePageModel::Observer,
                                     public RequestCoordinator::Observer {
  public:
   static bool Register(JNIEnv* env);
+  static std::unique_ptr<KeyedService> GetTestingRequestCoordinator(
+      content::BrowserContext* context);
 
   OfflinePageEvaluationBridge(JNIEnv* env,
                               content::BrowserContext* browser_context,