Convert ios_web_view_shell to pure Objective-C.

Convert ios_web_view_shell to pure Objective-C.

BUG=none

Review-Url: https://codereview.chromium.org/2659393004
Cr-Commit-Position: refs/heads/master@{#447141}
Committed: https://chromium.googlesource.com/chromium/src/+/8d0b6f3c626a8dc98dbb7fc9097a9c76dcb53bdc

[michaeldo, 2017-01-30 20:46:55]

michaeldo@chromium.org changed reviewers:
+ eugenebut@chromium.org

[michaeldo, 2017-01-30 20:46:56]

Note I removed the DCHECKS in translate_controller.m. Is there any reason to add
an assert in those places? I think we should remove them for now and add
nullability annotations in the future instead.

[Eugene But (OOO till 7-30), 2017-01-30 22:45:37]

lgtm

[michaeldo, 2017-01-30 23:02:19]

The CQ bit was checked by michaeldo@chromium.org

[commit-bot: I haz the power, 2017-01-30 23:03:24]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-31 00:50:55]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1485817339903660,
"parent_rev": "8c2e4456dc90138c5b5c34b8cb911b33de71b25e", "commit_rev":
"8d0b6f3c626a8dc98dbb7fc9097a9c76dcb53bdc"}

[commit-bot: I haz the power, 2017-01-31 00:51:37]

Description was changed from

==========
Convert ios_web_view_shell to pure Objective-C.

BUG=none
==========

to

==========
Convert ios_web_view_shell to pure Objective-C.

BUG=none

Review-Url: https://codereview.chromium.org/2659393004
Cr-Commit-Position: refs/heads/master@{#447141}
Committed:
https://chromium.googlesource.com/chromium/src/+/8d0b6f3c626a8dc98dbb7fc9097a...
==========

[commit-bot: I haz the power, 2017-01-31 00:51:38]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/8d0b6f3c626a8dc98dbb7fc9097a...