Deprecate some unused HTTP/2 histograms.

Deprecate unused histograms Net.SpdyRecvBytes, Net.SpdySendBytes,
Net.SpdyStreamDownloadTime, Net.SpdyStreamTime, and
Net.SpdyStreamTimeToFirstByte.

These take up a particularily large amount of space on our servers.

Bug: 750971, 764155, 773166, 777689, 779899, 800194, 804638, 807132, 813680, 831008, 838478, 845353, 878207, 884970, 891122, 908708, 915987, 918390, 921853, 940779, 948448, 953136
Change-Id: Iea6c3a6270b814d1eacec206cba40232d39b61fa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1584459
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Auto-Submit: Bence Béky <bnc@chromium.org>
Commit-Queue: Bence Béky <bnc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654310}
3 files changed