After removing histograms included in the internal histograms.xml, there are now "only" 130 that are not mapped.

Are you still working on this?

Not actively. I'm just using this as a tracking bug. Since the bugs are also in a hotlist, I can close this issue if you prefer.

I would recommend at least going through the bugs you filed and make sure the owners are still active on Chromium.

Sorry for the trouble. I just made a pass through and reassigned ones with inactive owners.

 Issue 387734  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b6543db89e2515c2f6ffb6cd58a07f603327cd44

commit b6543db89e2515c2f6ffb6cd58a07f603327cd44
Author: Mike Wittman <wittman@chromium.org>
Date: Fri May 18 23:57:44 2018

[Eraser] Remove Net.QuicClock.SkewOffset histogram

This was never added to histograms.xml, which means the data has never
been viewed on the dashboards. It's also among the top 10 unmapped
histograms by data size.

Since this was never used, this CL simply removes it.  There is no
reason to spend resources to record it.

BUG: 640921
Change-Id: I8d665d8797d6d7b8cbc69e7d64a3e390c89fa7df
Reviewed-on: https://chromium-review.googlesource.com/1066775
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Commit-Queue: Mike Wittman <wittman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560108}
[modify] https://crrev.com/b6543db89e2515c2f6ffb6cd58a07f603327cd44/net/quic/chromium/quic_clock_skew_detector.cc