Rename is_chromeos in chrome/src.

components/BUILD.gn

Index: components/BUILD.gn
diff --git a/components/BUILD.gn b/components/BUILD.gn
index e79db964c49ed34784c283a5d851b56907449923..cc00b1bed03ba4af2acfcd315bdd81213f962f02 100644
--- a/components/BUILD.gn
+++ b/components/BUILD.gn
@@ -152,14 +152,14 @@ group("all_components") {
   if (!is_win && !is_mac) {
     deps -= [ "//components/wifi" ]
   }
-  if (!is_chromeos) {
+  if (!use_cros_fe) {
     deps -= [
       "//components/pairing",
       "//components/wifi_sync",
     ]
   }
 
-  if (!is_chromeos || !enable_extensions) {
+  if (!use_cros_fe || !enable_extensions) {
     deps -= [ "//components/chrome_apps" ]
   }
 
@@ -371,7 +371,7 @@ test("components_unittests") {
     deps += [ "//components/proximity_auth:unit_tests" ]
   }
 
-  if (is_chromeos) {
+  if (use_cros_fe) {
     deps += [ "//components/ownership:unit_tests" ]
   }