Fix Histogram::FindCorruption() hang, part 2.

Like https://chromium-review.googlesource.com/c/585147/, this CL
removes more unused histograms that were causing hangs because
they were being logged in code that was holding a lock as a result
of https://chromium-review.googlesource.com/c/583228/.

BUG=748477,744734,736675
TBR=olivierrobin@chromium.org,pauljensen@chromium.org

Cq-Include-Trybots: master.tryserver.chromium.android:android_cronet_tester
Change-Id: Ie453687e866df98245d7e76298e2e757558b7825
Reviewed-on: https://chromium-review.googlesource.com/585297
Reviewed-by: Alexei Svitkine (slow) <asvitkine@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Commit-Queue: Alexei Svitkine (slow) <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#489465}
15 files changed