Rename is_chromeos in chrome/src.

content/browser/BUILD.gn

Index: content/browser/BUILD.gn
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index 39b66881f808c86039a60e84eb697731ab4c3fef..1a7b4458bb5b5ba3e845959b4319b8c00a8842f7 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -309,10 +309,10 @@ source_set("browser") {
   # Dealing with power_save_blocker_{x11,ozone}.cc is a little complicated
   # given the interaction between os_chromeos and the feature flags for X11 and
   # ozone, so do it all in one spot.
-  if (is_chromeos || !use_ozone) {
+  if (use_cros_fe || !use_ozone) {
     sources -= [ "power_save_blocker_ozone.cc" ]
   }
-  if (is_chromeos || !use_x11) {
+  if (use_cros_fe || !use_x11) {
     sources -= [ "power_save_blocker_x11.cc" ]
   }
 
@@ -321,7 +321,7 @@ source_set("browser") {
   if (is_android) {
     sources -= [ "geolocation/wifi_data_provider_common.cc" ]
   }
-  if (is_chromeos || (is_linux && !use_dbus)) {
+  if (use_cros_fe || (is_linux && !use_dbus)) {
     sources -= [ "geolocation/wifi_data_provider_linux.cc" ]
   }
   if (is_linux && use_dbus) {
@@ -396,7 +396,7 @@ source_set("browser") {
     ]
   }
 
-  if (is_chromeos) {
+  if (use_cros_fe) {
     sources -= [ "device_sensors/data_fetcher_shared_memory_default.cc" ]
     deps += [
       "//chromeos",