Use base::JSONReader::ReadDeprecated() in remoting/ and services/.

This is part of the process to help migrate base::JSONReader::Read() to
return base::Optional<base::Value>.

Do the same for ReadAndReturnError().

BUG=925165
TBR=blundell@chromium.org,garykac@chromium.org

Change-Id: I1c01449222ed7d310e1a5c05144d1a74f2fe5a4a
Reviewed-on: https://chromium-review.googlesource.com/c/1476076
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632879}
30 files changed