Updates to make install_third_party build gtest and gmock on windows.

build_tools/build_utils.py

 #!/usr/bin/python
 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that be
 # found in the LICENSE file.
 
 """Small utility library of python functions used by the various package
 installers.
 """
 
 import errno
@@ skipping 61 matching lines @@
 
   return shell_env
 
 
 # Return a "normalized" path that will work with both hermetic cygwin and *nix
 # shell environments.  On *nix, this method just returns the original path; on
 # Windows running hermetic cygwin, this alters the path.  |abs_path| must be
 # a fully-qualified absolute path, on Windows it must include the drive letter.
 # |shell_env| describes the environment used by any subprocess (this is
 # normally obtained from GetShellEnvironment()
-# TODO(dspringer,khim): make this work properly for hermetic cygwin (see bug
-# http://code.google.com/p/nativeclient/issues/detail?id=1122)
 def HermeticBuildPath(abs_path, shell_env):
   if (sys.platform == 'win32'):
-    return abs_path
+    return abs_path.replace('\\', '\\\\')
 
   return abs_path
 
 
 # patch version 2.6 doesn't work.  Most of our Linux distros use patch 2.6.
 # Returns |True| if the version of patch is usable (that is, not version 2.6).
 # |shell_env| is the enviromnent used to run the subprocesses like patch and
 # sed.  If |shell_env| is None, then os.environ is used.
 def CheckPatchVersion(shell_env=None):
   if shell_env is None:
@@ skipping 78 matching lines @@
   if m:
     return int(m.group(1))
   else:
     return 0
 
 # Returns the version of native client based on the svn revision number.
 def VersionString():
   rev = SVNRevision()
   build_number = os.environ.get('BUILD_NUMBER', '0')
   return 'native_client_sdk_0_1_%d_%s' % (rev, build_number)