Uncouple the cros_custom_toolchain from chromeos.

build/config/BUILDCONFIG.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.
 
 # =============================================================================
 # PLATFORM SELECTION
 # =============================================================================
 #
 # There are two main things to set: "os" and "cpu". The "toolchain" is the name
 # of the GN thing that encodes combinations of these things.
@@ skipping 127 matching lines @@
 
   # Compile for Leak Sanitizer to find leaks.
   is_lsan = false
 
   # Compile for Memory Sanitizer to find uninitialized reads.
   is_msan = false
 
   # Compile for Thread Sanitizer to find threading bugs.
   is_tsan = false
 
-  if (current_os == "chromeos") {
-    # Allows the target toolchain to be injected as arguments. This is needed
-    # to support the CrOS build system which supports per-build-configuration
-    # toolchains.
-    cros_use_custom_toolchain = false
-  }
+  # Allows the target toolchain to be injected as arguments. This is needed
+  # to support the CrOS build system which supports per-build-configuration
+  # toolchains.
+  cros_use_custom_toolchain = false

[Dirk Pranke, 2015/08/13 20:25:16]

if this is no longer strictly tied to CrOS, should this just be called
'use_custom_toolchain', etc.?

 
   # DON'T ADD MORE FLAGS HERE. Read the comment above.
 }
 
 # =============================================================================
 # OS DEFINITIONS
 # =============================================================================
 #
 # We set these various is_FOO booleans for convenience in writing OS-based
 # conditions.
@@ skipping 416 matching lines @@
     set_default_toolchain("//build/toolchain/android:$current_cpu")
   }
 } else if (is_linux) {
   if (is_clang) {
     host_toolchain = "//build/toolchain/linux:clang_$host_cpu"
     set_default_toolchain("//build/toolchain/linux:clang_$current_cpu")
   } else {
     host_toolchain = "//build/toolchain/linux:$host_cpu"
     set_default_toolchain("//build/toolchain/linux:$current_cpu")
   }
-  if (is_chromeos && cros_use_custom_toolchain) {
+  if (cros_use_custom_toolchain) {
     set_default_toolchain("//build/toolchain/cros:target")
   }
 } else if (is_mac) {
   host_toolchain = "//build/toolchain/mac:clang_x64"
   set_default_toolchain(host_toolchain)
 } else if (is_ios) {
   host_toolchain = "//build/toolchain/mac:clang_x64"
   set_default_toolchain("//build/toolchain/mac:ios_clang_arm")
 } else if (is_nacl) {
   # TODO(GYP): This will need to change when we get NaCl working
@@ skipping 17 matching lines @@
     forward_variables_from(invoker, "*")
 
     # All shared libraries must have the sanitizer deps to properly link in
     # asan mode (this target will be empty in other cases).
     if (!defined(deps)) {
       deps = []
     }
     deps += [ "//build/config/sanitizers:deps" ]
   }
 }