Remove the first launch from home screen requirement for notification deep linking.

https://crrev.com/1867543002 implemented notification deep linking for
Android, with the requirement that a web app be explicily launched from
home screen before it would be permitted to have deep links from
notifications. This CL removes this requirement. Now sites which have
been added to homescreen OR launched from homescreen within the
last ten days are permitted to be deep-linked from a notification.

BUG=541711

Review URL: https://codereview.chromium.org/1872983002

Cr-Commit-Position: refs/heads/master@{#386381}
4 files changed