Make WebContents::GetOuterWebContents() const.

Change-Id: I60d5a327f7f0ad22dccdbdcbe15dbfaf89f98918
Reviewed-on: https://chromium-review.googlesource.com/c/1302493
Reviewed-by: Alex Moshchuk <[email protected]>
Commit-Queue: Lucas Gadani <[email protected]>
Cr-Commit-Position: refs/heads/master@{#603972}
5 files changed