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Code and tests are mostly carried over from settings/languages_page,
with small change to Retry button aria-label.
Will add other components in following CLs.
Current view: http://screen/35HsGe5kNDds66q
View when spell check is disabled: http://screen/3maPBnjn24GPJaj

Note: All strings are not finalised so they are translateable false
and no screenshots required.
Minor changes to jsdoc.

Bug: 1113439
Change-Id: I998e65f02c2452c41fddb75ca6ade74de0c3e049
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2359972
Commit-Queue: My Nguyen <myy@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Regan Hsu <hsuregan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805645}