Add documentation for the chrome.sockets API and manifest key.

extensions/common/permissions/api_permission.h

 // Copyright 2013 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 EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_
 #define EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 114 matching lines @@
     kProcesses,
     kProxy,
     kPushMessaging,
     kImageWriterPrivate,
     kRtcPrivate,
     kSearchProvider,
     kSerial,
     kSessions,
     kSignedInDevices,
     kSocket,
-    kSocketsUdp,
     kStartupPages,
     kStorage,
     kStreamsPrivate,
     kSyncFileSystem,
     kSystemPrivate,
     kSystemIndicator,
     kSystemDisplay,
     kSystemStorage,
     kTab,
     kTabCapture,
@@ skipping 188 matching lines @@
   const char* const name_;
   const int flags_;
   const int l10n_message_id_;
   const PermissionMessage::ID message_id_;
   const APIPermissionConstructor api_permission_constructor_;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_PERMISSIONS_API_PERMISSION_H_