refactor: cc::LapTimer => base::LapTimer

Makes LapTimer (which provides a runs per second figure) accessible to
base_perftests benchmarks by updating it and moving it into base/.

Bug: 908966
Change-Id: I7913ea8e37b04d5309bed577dbdc54d98df971c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1353950
Reviewed-by: Dan Erat <[email protected]>
Reviewed-by: Tibor Goldschwendt <[email protected]>
Reviewed-by: Trent Apted <[email protected]>
Reviewed-by: Sami Kyöstilä <[email protected]>
Reviewed-by: François Doray <[email protected]>
Reviewed-by: danakj <[email protected]>
Commit-Queue: Richard Townsend <[email protected]>
Cr-Commit-Position: refs/heads/master@{#638100}
33 files changed