GitLab

Set the network quality in the client hints to the holdback
value if network quality web holdback experiment is enabled.

Change-Id: Ifc6bcef11c9f980c340d4286e4472572e871f6f7
Bug: 880545
Reviewed-on: https://chromium-review.googlesource.com/c/1227684Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Tarun Bansal <tbansal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#595924}