Revert of [profiler] Add extra CHECK to track down crbug.com/665398 (patchset #1 id:1 of https://codereview.chromium.org/2556833003/ )

Reason for revert:
Not needed anymore. The bug is fixed.

Original issue's description:
> [profiler] Add extra CHECK to track down crbug.com/665398
>
> BUG=chromium:665398
>
> Committed: https://crrev.com/dfc0bb63a1bc115d39f29cfc338aed5676578c4b
> Cr-Commit-Position: refs/heads/master@{#41545}

TBR=yangguo@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:665398

Review-Url: https://codereview.chromium.org/2588973003
Cr-Commit-Position: refs/heads/master@{#41830}