Change Object::GetPropertyNames/GetOwnPropertyNames from
V8_DEPRECATE_SOON to V8_DEPRECATED.

Bug: v8:7286, v8:8562
Change-Id: I2c601e6bf729e8fb68be8bc9a7b1618da61934af
Reviewed-on: https://chromium-review.googlesource.com/c/1393285Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58624}