Cleanup script using Python instead of rm command.

BUG=None
TEST=Ran the script on all platforms and a Linux master+slave build.

Review URL: https://webrtc-codereview.appspot.com/479008

git-svn-id: http://webrtc.googlecode.com/svn/trunk@2010 4adac7df-926f-26a2-2b94-8c16560cd09d

tools/continuous_build/build_internal/site_config/config_private.py

@@ -24,6 +24,7 @@ class Master(object):
 
   # Directly fetches from anonymous webkit svn server.
   webkit_root_url = 'http://svn.webkit.org/repository/webkit'
+  nacl_trunk_url = 'http://src.chromium.org/native_client/trunk'
 
   llvm_url = 'http://llvm.org/svn/llvm-project'