Introduce chrome.displaySource API

extensions/browser/extension_event_histogram_value.h

 // Copyright 2015 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_BROWSER_EXTENSION_EVENT_HISTOGRAM_VALUE_H_
 #define EXTENSIONS_BROWSER_EXTENSION_EVENT_HISTOGRAM_VALUE_H_
 
 namespace extensions {
 namespace events {
 
@@ skipping 392 matching lines @@
   CAST_DEVICES_PRIVATE_ON_STOP_CAST,
   CERTIFICATEPROVIDER_ON_CERTIFICATES_REQUESTED,
   CERTIFICATEPROVIDER_ON_SIGN_DIGEST_REQUESTED,
   WEB_VIEW_INTERNAL_ON_AUTH_REQUIRED,
   WEB_VIEW_INTERNAL_ON_BEFORE_REDIRECT,
   WEB_VIEW_INTERNAL_ON_ERROR_OCCURRED,
   WEB_VIEW_INTERNAL_ON_SEND_HEADERS,
   EASY_UNLOCK_PRIVATE_ON_CONNECTION_STATUS_CHANGED,
   EASY_UNLOCK_PRIVATE_ON_DATA_RECEIVED,
   EASY_UNLOCK_PRIVATE_ON_SEND_COMPLETED,
+  DISPLAY_SOURCE_ON_SINKS_UPDATED,
   // Last entry: Add new entries above, then run:
   // python tools/metrics/histograms/update_extension_histograms.py
   ENUM_BOUNDARY
 };
 
 }  // namespace events
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSION_EVENT_HISTOGRAM_VALUE_H_