[Extensions] Update a bunch of tests to manifest v2

We should (finally) remove support for manifest v1. One of the last
significant dependencies is that a lot of our tests aren't manifest v2
yet.

This CL updates the majority of manifest.json files under
chrome/test/data/extensions. This CL only modifies files that update
cleanly (i.e., no other test updates necessary). A separate CL will
address those.

Bug: 816679

Change-Id: I0ae5a47efd9929c5db2c74d58e4d04de7099ef1c
Reviewed-on: https://chromium-review.googlesource.com/938261
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540081}
256 files changed