Minor cleanups in the web/ Notification files.

BUG=None
TEST=None
R=peter@chromium.org,tkent@chromium.org

Review URL: https://codereview.chromium.org/456563002

git-svn-id: svn://svn.chromium.org/blink/trunk@179812 bbb929c8-8fbe-4397-9dbb-9b2b20218538