Cleanups in remoting gn files.

remoting/remoting_enable.gni

 # 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.
 
 import("//build/config/ui.gni")
+import("//media/media_options.gni")
 
 declare_args() {
-  enable_remoting = !is_ios && !is_chromecast
+  enable_remoting = !is_ios && !is_chromecast && enable_webrtc
 }
-
-enable_remoting_host = false
-enable_me2me_host = false
-
-if (is_win || (is_linux && !is_chromeos && use_x11) || is_mac) {
-  enable_remoting_host = true
-  enable_me2me_host = true
-}
-
-if (is_linux && is_chromeos) {
-  enable_remoting_host = true
-}