Convert SafeJsonParser to use new base::Value API

Change SafeJsonParser to pass the base::Value by values instead
of using std::unique_ptr<base::Value>.

Bug: 959749
Change-Id: Ia23cc6036a114d25f4cc1e21fc5ea0feb8de1f8d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1609820
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661684}
59 files changed