GitLab

With the NG trybots using the buildbot value, browser_tests' sharding value regressed from the original 8 to 5 shards. The bots are now seeing more delays. Bump everything up to 10.

R=maruel@chromium.org

Review URL: https://codereview.chromium.org/805913004

Cr-Commit-Position: refs/heads/master@{#308408}