Suppress warnings in the new SCons version about an obscure

possible Windows race condition (file handles being held open an
indeterminate amount of time after being closed in other threads).

R: mpcomplete
Review URL: http://codereview.chromium.org/2940

git-svn-id: http://src.chromium.org/svn/trunk/src/build@2325 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

SConscript.main

@@ -14,7 +14,8 @@ elif p == 'name':
   Progress('$TARGET\r', overwrite=True, file=open('con', 'w'))
 
 
-SetOption('warn', ['no-missing-sconscript'] + GetOption('warn'))
+default_warnings = ['no-missing-sconscript', 'no-no-parallel-support']
+SetOption('warn', default_warnings + GetOption('warn'))
 
 
 load = ARGUMENTS.get('LOAD')