Revert of [Chromecast] Change chromecast_branding to public

chromecast/media/base/BUILD.gn

 # 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/crypto.gni")
 import("//chromecast/chromecast.gni")
 
 declare_args() {
   libcast_media_target = ""
 }
@@ skipping 17 matching lines @@
   configs += [ "//chromecast:config" ]
 
   deps = [
     "//base",
     "//crypto",
     "//crypto:platform",
     "//media",
     "//third_party/widevine/cdm:version_h",
   ]
 
-  if (chromecast_branding != "public") {
+  if (is_chromecast_chrome_branded) {
     deps += [
       "${libcast_media_target}",
       # TODO(gyp): add dependency on internal/chromecast_internal:media_base_internal
     ]
   } else {
     sources += [ "key_systems_common_simple.cc" ]
 
     deps += [ ":libcast_media_default" ]
   }
 }
 
 shared_library("libcast_media_default") {
   output_name = "libcast_media_1.0"
 
   sources = [
     "cast_media_default.cc",
   ]
 
   configs += [ "//chromecast:config" ]
 
   deps = [
     "//chromecast/public",
   ]
 }