[WebRTC] Add ScreenCapturerDifferWrapper to share Differ across ScreenCapturers

webrtc/modules/desktop_capture/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/ui.gni")
 import("../../build/webrtc.gni")
@@ skipping 44 matching lines @@
     "mac/scoped_pixel_buffer_object.h",
     "mac/window_list_utils.cc",
     "mac/window_list_utils.h",
     "mouse_cursor.cc",
     "mouse_cursor.h",
     "mouse_cursor_monitor.h",
     "mouse_cursor_monitor_mac.mm",
     "mouse_cursor_monitor_win.cc",
     "screen_capture_frame_queue.h",
     "screen_capturer.h",
+    "screen_capturer_differ_wrapper.cc",
+    "screen_capturer_differ_wrapper.h",
     "screen_capturer_helper.cc",
     "screen_capturer_helper.h",
     "screen_capturer_mac.mm",
     "screen_capturer_win.cc",
     "shared_desktop_frame.cc",
     "shared_desktop_frame.h",
     "shared_memory.cc",
     "shared_memory.h",
     "win/cursor.cc",
     "win/cursor.h",
@@ skipping 83 matching lines @@
     ]
 
     configs += [ "../..:common_config" ]
     public_configs = [ "../..:common_inherited_config" ]
 
     if (is_posix && !is_mac) {
       cflags = [ "-msse2" ]
     }
   }
 }