R=yangguo@chromium.org
BUG=v8:2177
TEST=mjsunit/debug-liveedit-breakpoints

Review URL: https://chromiumcodereview.appspot.com/10543112

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11776 ce2b1a6d-e550-0410-aec6-3dcde31c8c00