icecc support for cros host build

build/toolchain/cros/BUILD.gn

 # Copyright 2014 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/compiler/compiler.gni")
 import("//build/config/sysroot.gni")
 import("//build/toolchain/gcc_toolchain.gni")
 import("//build/toolchain/cros_toolchain.gni")
 
 # This is the normal toolchain for most targets.
 gcc_toolchain("target") {
   ar = cros_target_ar
   cc = cros_target_cc
   cxx = cros_target_cxx
   ld = cxx
   if (cros_target_ld != "") {
     ld = cros_target_ld
   }
   if (cros_target_nm != "") {
     nm = cros_target_nm
   }
   if (cros_target_readelf != "") {
     readelf = cros_target_readelf
   }
+  if (cc_wrapper != "") {
+    print("cc_wrapper is not supported on target build. crbug.com/645435")
+  }
   extra_cflags = cros_target_extra_cflags
   extra_cppflags = cros_target_extra_cppflags
   extra_cxxflags = cros_target_extra_cxxflags
   extra_ldflags = cros_target_extra_ldflags
 
   toolchain_args = {
     cc_wrapper = ""
     current_cpu = target_cpu
     current_os = "chromeos"
     is_clang = is_clang
@@ skipping 31 matching lines @@
     current_cpu = target_cpu
     current_os = "chromeos"
     is_clang = is_clang
     use_debug_fission = false
     use_gold = false
     use_sysroot = false
   }
 }
 
 gcc_toolchain("host") {
+  if (cc_wrapper != "") {
+    compiler_prefix = cc_wrapper + " "
+  } else {
+    compiler_prefix = ""
+  }
+
   # These are args for the template.
   ar = cros_host_ar
-  cc = cros_host_cc
-  cxx = cros_host_cxx
+  cc = compiler_prefix + cros_host_cc
+  cxx = compiler_prefix + cros_host_cxx
   ld = cxx
   if (cros_host_ld != "") {
     ld = cros_host_ld
   }
   if (cros_host_nm != "") {
     nm = cros_host_nm
   }
   if (cros_host_readelf != "") {
     readelf = cros_host_readelf
   }
@@ skipping 37 matching lines @@
     if (target_cpu == "x86" || target_cpu == "arm" || target_cpu == "mipsel") {
       current_cpu = "x86"
     } else {
       current_cpu = "x64"
     }
     v8_current_cpu = v8_target_cpu
     current_os = "linux"
     use_sysroot = false
   }
 }