This new method only compares Strings and so doesn't need a Context. It
also can't throw so it returns bool. Can be used in place of the
deprecated Equals method and many Equals call currently taking a
Context.

Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: I4cfe7747aa140e5a55d9513681ee4704414e1545
Reviewed-on: https://chromium-review.googlesource.com/1151321
Commit-Queue: Dan Elphick <delphick@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54812}