Add browser test for encryption migration flows

Bug: 949231
Change-Id: Id984f2aeaa0201b96f296f5e3e1ff4919e4d7038
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1578004
Reviewed-by: Pavol Marko <pmarko@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Toni Baržić <tbarzic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653780}
13 files changed