clang/win: Fix warnings to prepare for building without -Wno-reorder.

build/secondary/testing/gtest/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.
 
 config("gtest_config") {
   visibility = [
     ":*",
     "//testing/gmock:*",  # gmock also shares this config.
   ]
 
   defines = [
     # In order to allow regex matches in gtest to be shared between Windows
     # and other systems, we tell gtest to always use it's internal engine.
     "GTEST_HAS_POSIX_RE=0",
 
     # Chrome doesn't support / require C++11, yet.
     "GTEST_LANG_CXX11=0",
   ]
 
   # Gtest headers need to be able to find themselves.
   include_dirs = [ "include" ]
 
   if (is_win) {
     cflags = [ "/wd4800" ]  # Unused variable warning.
+    if (is_clang) {
+      # The Mutex constructor initializer list in gtest-port.cc is incorrectly
+      # ordered.

[Nico, 2015/06/30 18:03:50]

Can you file an upstream bug for this?

[Sam McNally, 2015/07/02 00:12:13]

Done.

+      cflags += [ "-Wno-reorder" ]
+    }
   }
 
   if (is_posix) {
     defines += [
       # gtest isn't able to figure out when RTTI is disabled for gcc
       # versions older than 4.3.2, and assumes it's enabled.  Our Mac
       # and Linux builds disable RTTI, and cannot guarantee that the
       # compiler will be 4.3.2. or newer.  The Mac, for example, uses
       # 4.2.1 as that is the latest available on that platform.  gtest
       # must be instructed that RTTI is disabled here, and for any
@@ skipping 81 matching lines @@
 source_set("gtest_main") {
   # TODO http://crbug.com/412064 enable this flag all the time.
   testonly = !is_component_build
   sources = [
     "src/gtest_main.cc",
   ]
   deps = [
     ":gtest",
   ]
 }