GitLab

Allows to collect profiling data from several page loads, and to scroll
the screen while doing so.

Bug: 758566
Change-Id: I4f0bb8fc167e69dea349dbd4b5ee733193996e41
Reviewed-on: https://chromium-review.googlesource.com/801016
Commit-Queue: Benoit L <lizeb@chromium.org>
Reviewed-by: Egor Pasko <pasko@chromium.org>
Reviewed-by: Matthew Cary <mattcary@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522392}