Test that console.time/End/Stamp properly show up in the log file.

Change-Id: I99904e20fc98811ed3e3b5e5a9d186b459b8d4be
Reviewed-on: https://chromium-review.googlesource.com/743020
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49035}