This is a quick fix for gclient runhooks error on Mac/Linux.

BUG=
TEST=gclient runhooks --force on Mac/Linux
Review URL: https://codereview.appspot.com/5732047

git-svn-id: https://angleproject.googlecode.com/svn/trunk@997 736b8ea6-26fd-11df-bfd4-992fa37f6226