Fix remoting_webapp build script after r278198.

webapp_build.py wasn't updated properly in r278198. As result main.html
wasn't properly package in the webapp.

TBR=wez@chromium.org
BUG=134215

Review URL: https://codereview.chromium.org/344753002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278218 0039d316-1c4b-4281-b951-d872f2087c98

remoting/webapp/build-webapp.py

@@ -272,7 +272,7 @@ def main():
   arg_type = ''
   files = []
   locales = []
-  for arg in sys.argv[8:]:
+  for arg in sys.argv[7:]:
     if arg in ['--locales']:
       arg_type = arg
     elif arg_type == '--locales':