GitLab

This CL removes most of guava, except a few classes and annotations.

Also updates the rest of Chrome to ensure only those classes are in use.

Thirdly, it adds an OWNERS file to third_party/guava.

BUG=163393
TBR=brettw@chromium.org

Review URL: https://codereview.chromium.org/546973003

Cr-Commit-Position: refs/heads/master@{#293828}