Rename is_chromeos in chrome/src.

media/mojo/interfaces/BUILD.gn

Index: media/mojo/interfaces/BUILD.gn
diff --git a/media/mojo/interfaces/BUILD.gn b/media/mojo/interfaces/BUILD.gn
index 1f9b19b13fc8aba30d60561fa62ccfd21f8d8a5c..82a347f33465f6809957ba0d8776aab871f66df8 100644
--- a/media/mojo/interfaces/BUILD.gn
+++ b/media/mojo/interfaces/BUILD.gn
@@ -2,6 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/features.gni")
 import("//third_party/mojo/src/mojo/public/tools/bindings/mojom.gni")
 
 mojom("interfaces") {
@@ -14,7 +15,7 @@ mojom("interfaces") {
     "service_factory.mojom",
   ]
 
-  if (is_chromeos) {
+  if (use_cros_fe) {
     sources += [ "platform_verification.mojom" ]
   }