Move Singleton and related structs to namespace base

content/browser/android/download_controller_android_impl.h

 // Copyright (c) 2012 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.
 
 // This class pairs with DownloadController on Java side to forward requests
 // for GET downloads to the current DownloadListener. POST downloads are
 // handled on the native side.
 //
 // Both classes are Singleton classes. C++ object owns Java object.
 //
@@ skipping 65 matching lines @@
     std::string original_mime_type;
     std::string user_agent;
     std::string cookie;
     std::string referer;
     bool has_user_gesture;
 
     WebContents* web_contents;
     // Default copy constructor is used for passing this struct by value.
   };
   struct JavaObject;
-  friend struct DefaultSingletonTraits<DownloadControllerAndroidImpl>;
+  friend struct base::DefaultSingletonTraits<DownloadControllerAndroidImpl>;
   DownloadControllerAndroidImpl();
   ~DownloadControllerAndroidImpl() override;
 
   // Helper method for implementing AcquireFileAccessPermission().
   bool HasFileAccessPermission(
       base::android::ScopedJavaLocalRef<jobject> j_content_view_core);
 
   // DownloadControllerAndroid implementation.
   void CreateGETDownload(int render_process_id,
                          int render_view_id,
@@ skipping 46 matching lines @@
   JavaObject* java_object_;
 
   ScopedVector<DeferredDownloadObserver> deferred_downloads_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadControllerAndroidImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_DOWNLOAD_CONTROLLER_ANDROID_IMPL_H_