Quota: Remove define macro used for callback cleanup

Depends on: https://codereview.chromium.org/155283003/


BUG=338995
TEST=compile

Review URL: https://codereview.chromium.org/140433007

git-svn-id: svn://svn.chromium.org/blink/trunk@166804 bbb929c8-8fbe-4397-9dbb-9b2b20218538