Rename is_chromeos in chrome/src.

device/usb/BUILD.gn

Index: device/usb/BUILD.gn
diff --git a/device/usb/BUILD.gn b/device/usb/BUILD.gn
index edb8c93cbb1cc85598cc83464fef07ae101a9073..7e968dce6a62e3188eb819cf45d91b3c6d001616 100644
--- a/device/usb/BUILD.gn
+++ b/device/usb/BUILD.gn
@@ -2,6 +2,8 @@
 # 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")
+
 assert(!is_android && !is_ios)
 
 source_ids = "//third_party/usb_ids/usb.ids"
@@ -48,7 +50,7 @@ source_set("usb") {
   if (is_linux) {
     deps += [ "//device/udev_linux" ]
   }
-  if (is_chromeos) {
+  if (use_cros_fe) {
     deps += [
       "//chromeos",
       "//dbus",