Update PermissionContextBaseTests for permission bubble

This makes the PermissionContextBaseTests tests work both with and
without the permission bubble, in preparation for flipping the flag.

Supercedes https://codereview.chromium.org/411503005/

BUG=438758

Review URL: https://codereview.chromium.org/800853004

Cr-Commit-Position: refs/heads/master@{#308522}
2 files changed