Rename is_chromeos in chrome/src.

ui/base/BUILD.gn

Index: ui/base/BUILD.gn
diff --git a/ui/base/BUILD.gn b/ui/base/BUILD.gn
index 15ad86c835b844328f628e0acf325ae16b329a6b..effd2cae7353ca8a3f1f11636023831b2ab624ac 100644
--- a/ui/base/BUILD.gn
+++ b/ui/base/BUILD.gn
@@ -365,7 +365,7 @@ component("base") {
       "x/x11_util.h",
       "x/x11_util_internal.h",
     ]
-    if (!is_chromeos) {
+    if (!use_cros_fe) {
       sources += [
         "idle/idle_query_x11.cc",
         "idle/idle_query_x11.h",
@@ -392,7 +392,7 @@ component("base") {
     ]
   }
 
-  if ((is_linux && !is_chromeos) || is_chromeos) {
+  if ((is_linux && !use_cros_fe) || use_cros_fe) {
     if (!toolkit_views && !use_aura) {
       sources -= [
         "dragdrop/drag_utils.cc",
@@ -401,12 +401,12 @@ component("base") {
     }
   }
 
-  if (is_chromeos) {
+  if (use_cros_fe) {
     deps += [ "//chromeos" ]
     sources -= [ "idle/idle_linux.cc" ]
   }
 
-  if (is_chromeos || (use_aura && ((is_linux && !use_x11) || is_android))) {
+  if (use_cros_fe || (use_aura && ((is_linux && !use_x11) || is_android))) {
     sources += [
       "dragdrop/os_exchange_data_provider_aura.cc",
       "dragdrop/os_exchange_data_provider_aura.h",
@@ -478,7 +478,7 @@ component("base") {
         "cursor/cursor_loader_x11.h",
         "cursor/cursor_x11.cc",
       ]
-      if (!is_chromeos) {
+      if (!use_cros_fe) {
         # These Aura X11 files aren't used on ChromeOS.
         sources += [
           "dragdrop/os_exchange_data_provider_aurax11.cc",
@@ -713,13 +713,13 @@ test("ui_base_unittests") {
       "ime/win/imm32_manager_unittest.cc",
       "ime/win/tsf_input_scope_unittest.cc",
     ]
-    if (is_linux && use_aura && !is_chromeos) {
+    if (is_linux && use_aura && !use_cros_fe) {
       sources += [ "ime/input_method_auralinux_unittest.cc" ]
     }
     if (use_x11) {
       sources += [ "ime/composition_text_util_pango_unittest.cc" ]
     }
-    if (!use_x11 && is_chromeos) {
+    if (!use_x11 && use_cros_fe) {
       # These were already removed in the non-chromeos case.
       sources -= [ "ime/input_method_chromeos_unittest.cc" ]
     }
@@ -817,14 +817,14 @@ test("ui_base_unittests") {
     ]
   }
 
-  if (use_x11 && !is_chromeos) {
+  if (use_x11 && !use_cros_fe) {
     sources += [
       "dragdrop/os_exchange_data_provider_aurax11_unittest.cc",
       "x/selection_requestor_unittest.cc",
     ]
   }
 
-  if (is_chromeos) {
+  if (use_cros_fe) {
     deps += [
       "//chromeos",
       "//ui/events:dom_keycode_converter",