[Extensions] Remove manifest v1 support for page actions

In manifest v1, page actions had support for different keys, including
a list of icons (instead of a single icon), "popup"
(vs "default_popup"), "name" (vs "default_title"), "type" (deprecated),
and "id" (deprecated).

Remove parsing support for the deprecated keys. Update unit tests
to manifest v2 where applicable, and remove manifest v1-specific
tests.

Bug: 816677, 816679
Change-Id: Id4db2558e0f5b9006c89a0f3ef89aed230a7b359
Reviewed-on: https://chromium-review.googlesource.com/953179
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542590}
19 files changed