Move downloads API to extensions namespace

chrome/browser/extensions/api/downloads/downloads_api.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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_
 
 #include <set>
 #include <string>
 
@@ skipping 48 matching lines @@
 extern const char kNotResumable[];
 extern const char kOpenPermission[];
 extern const char kShelfDisabled[];
 extern const char kShelfPermission[];
 extern const char kTooManyListeners[];
 extern const char kUnexpectedDeterminer[];
 extern const char kUserGesture[];
 
 }  // namespace download_extension_errors
 
+namespace extensions {
 
 class DownloadedByExtension : public base::SupportsUserData::Data {
  public:
   static DownloadedByExtension* Get(content::DownloadItem* item);
 
   DownloadedByExtension(content::DownloadItem* item,
                         const std::string& id,
                         const std::string& name);
 
   const std::string& id() const { return id_; }
@@ skipping 316 matching lines @@
   std::set<const extensions::Extension*> shelf_disabling_extensions_;
 
   // Listen to extension unloaded notifications.
   ScopedObserver<extensions::ExtensionRegistry,
                  extensions::ExtensionRegistryObserver>
       extension_registry_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionDownloadsEventRouter);
 };
 
+}  // namespace extensions
+
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DOWNLOADS_DOWNLOADS_API_H_