Make toolchain2013.py work properly if there's a space in the temp path.

win_toolchain/toolchain2013.py

 #!/usr/bin/env python
 # Copyright 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.
 
 """Extracts a Windows VS2013 toolchain from various downloadable pieces."""
 
 
 import ctypes
 import json
@@ skipping 178 matching lines @@
   target_path = os.path.join(sdk_temp_dir, 'sdksetup.exe')
   standalone_path = os.path.join(sdk_temp_dir, 'Standalone')
   Download(
       ('http://download.microsoft.com/download/'
        'F/1/3/F1300C9C-A120-4341-90DF-8A52509B23AC/standalonesdk/sdksetup.exe'),
       target_path)
   sys.stdout.write(
       'Running sdksetup.exe to download Win8 SDK (may request elevation)...\n')
   count = 0
   while count < 5:
-    rc = os.system(target_path + ' /quiet '
-                   '/features OptionId.WindowsDesktopDebuggers '
-                             'OptionId.WindowsDesktopSoftwareDevelopmentKit '
-                   '/layout ' + standalone_path)
+    rc = subprocess.call([target_path,
+                          '/quiet',
+                          '/features', 'OptionId.WindowsDesktopDebuggers',
+                              'OptionId.WindowsDesktopSoftwareDevelopmentKit',
+                          '/layout', standalone_path])
     if rc == 0:
       return standalone_path
     count += 1
     sys.stdout.write('Windows 8 SDK failed to download, retrying.\n')
   sys.exit('After multiple retries, couldn\'t download Win8 SDK')
 
 
 def DownloadWDKIso():
   wdk_temp_dir = TempDir()
   target_path = os.path.join(wdk_temp_dir, 'GRMWDK_EN_7600_1.ISO')
@@ skipping 270 matching lines @@
     }
     with open(os.path.join(target_dir, '..', 'data.json'), 'w') as f:
       json.dump(data, f)
   finally:
     if options.clean:
       DeleteAllTempDirs()
 
 
 if __name__ == '__main__':
   sys.exit(main())