GitLab

* Changed FPSGraphPageView to observe the PresentationFeedback
* Reset the data when refresh rate changes because the data before
  change is not relevant anymore.

Bug: None
Change-Id: I4e0d8ef860b99255e2c6ad10d8f845a1e18c0ac9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2517779Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824540}