Remove unused variable from vs_toolchain.py

build/vs_toolchain.py

 #!/usr/bin/env python
 # 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 glob
 import json
 import os
 import pipes
 import platform
@@ skipping 384 matching lines @@
 
 def NormalizePath(path):
   while path.endswith("\\"):
     path = path[:-1]
   return path
 
 
 def SetEnvironmentAndGetSDKDir():
   """Gets location information about the current sdk (must have been
   previously updated by 'update'). This is used for the GN build."""
-  runtime_dll_dirs = SetEnvironmentAndGetRuntimeDllDirs()
+  SetEnvironmentAndGetRuntimeDllDirs()
 
   # If WINDOWSSDKDIR is not set, search the default SDK path and set it.
   if not 'WINDOWSSDKDIR' in os.environ:
     default_sdk_path = 'C:\\Program Files (x86)\\Windows Kits\\10'
     if os.path.isdir(default_sdk_path):
       os.environ['WINDOWSSDKDIR'] = default_sdk_path
 
   return NormalizePath(os.environ['WINDOWSSDKDIR'])
 
 
@@ skipping 23 matching lines @@
       'copy_dlls': CopyDlls,
   }
   if len(sys.argv) < 2 or sys.argv[1] not in commands:
     print >>sys.stderr, 'Expected one of: %s' % ', '.join(commands)
     return 1
   return commands[sys.argv[1]](*sys.argv[2:])
 
 
 if __name__ == '__main__':
   sys.exit(main())