Use std::unique_ptr for base::DictionaryValue and base::ListValue's internal store.

BUG=581865
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
R=brettw@chromium.org,danakj@chromium.org
TBR=kenrb@chromium.org,stevenjb@chromium.org

Review-Url: https://codereview.chromium.org/2000803003
Cr-Commit-Position: refs/heads/master@{#395938}
80 files changed