Rename is_chromeos in chrome/src.

build/config/compiler/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/chrome_build.gni")
 if (current_cpu == "arm") {
   import("//build/config/arm.gni")
 }
 if (current_cpu == "mipsel" || current_cpu == "mips64el") {
@@ skipping 160 matching lines @@
 
       # Not exporting C++ inline functions can generally be applied anywhere
       # so we do so here. Normal function visibility is controlled by
       # //build/config/gcc:symbol_visibility_hidden.
       "-fvisibility-inlines-hidden",
     ]
 
     # Stack protection.
     if (is_mac) {
       cflags += [ "-fstack-protector-all" ]
-    } else if (is_posix && !is_chromeos && !is_nacl) {
+    } else if (is_posix && !is_chromeos_ui && !is_nacl) {
       # TODO(phajdan.jr): Use -fstack-protector-strong when our gcc supports it.
       cflags += [ "--param=ssp-buffer-size=4" ]
       if (is_android && (current_cpu == "arm64" || current_cpu == "x86")) {
         cflags += [ "-fno-stack-protector" ]
       } else {
         cflags += [ "-fstack-protector" ]
       }
     }
 
     # Linker warnings.
-    if (!(is_chromeos && current_cpu == "arm") && !is_mac && !is_ios) {
+    if (!(is_chromeos_os && current_cpu == "arm") && !is_mac && !is_ios) {
       # TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
       ldflags += [ "-Wl,--fatal-warnings" ]
     }
 
     # Common options for AddressSanitizer, LeakSanitizer, ThreadSanitizer and
     # MemorySanitizer
     if (using_sanitizer) {
       cflags += [
         "-fno-omit-frame-pointer",
         "-gline-tables-only",
@@ skipping 288 matching lines @@
       #"-Wl,--threads",
       #"-Wl,--thread-count=4",
     ]
 
     if (!is_asan && !is_msan && !is_lsan && !is_tsan) {
       # TODO(brettw) common.gypi has this only for target toolset.
       ldflags += [ "-Wl,--icf=all" ]
     }
 
     # TODO(thestig): Make this flag work with GN.
-    #if (!is_official_build && !is_chromeos && !(is_asan || is_lsan || is_tsan || is_msan)) {
+    #if (!is_official_build && !is_chromeos_os && !(is_asan || is_lsan || is_tsan || is_msan)) {
     #  ldflags += [
     #    "-Wl,--detect-odr-violations",
     #  ]
     #}
   }
 
   if (linux_use_bundled_binutils) {
     cflags += [ "-B$binutils_path" ]
   }
 
@@ skipping 617 matching lines @@
 # regardless of whether what they point to is already known to be valid.
 # gcc 4.9 and earlier had no way of suppressing this warning without
 # supressing the rest of them.  Here we centralize the identification of
 # the gcc 4.9 toolchains.
 config("no_incompatible_pointer_warnings") {
   cflags = []
   if (is_clang) {
     cflags += [ "-Wno-incompatible-pointer-types" ]
   } else if (current_cpu == "mipsel") {
     cflags += [ "-w" ]
-  } else if (is_chromeos && current_cpu == "arm") {
+  } else if (is_chromeos_os && current_cpu == "arm") {
     cflags += [ "-w" ]
   }
 }
 
 # Optimization -----------------------------------------------------------------
 #
 # Note that BUILDCONFIG.gn sets up a variable "default_optimization_config"
 # which it will assign to the config it implicitly applies to every target. If
 # you want to override the optimization level for your target, remove this
 # config (which will expand differently for debug or release builds), and then
@@ skipping 182 matching lines @@
       cflags += [ "-gsplit-dwarf" ]
     }
   }
 }
 
 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }