Remove and extend some histograms.

Extend the following histograms by 1 year since they are still useful:
SafeBrowsing.RT.HasTokenInRequest*
SB2.DownloadUrlCheckDuration*

Remove the following histograms and their relevant code since they are
not used anymore:
SBClientDownload.SafeDownloadOpenedLatencyByContentType.*
SBClientDownload.UserGestureFileType.LastBypassDownloadInterval*
Download.Bubble.DragInfo*

OBSOLETE_HISTOGRAMS=Histograms no longer used

Fixed: 1474443,1474444,1476586,1481132,1488538
Change-Id: I6aba0e8f7c51e7a94c5e9daba484f58dc63a529b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4933178
Reviewed-by: Min Qin <qinmin@chromium.org>
Reviewed-by: Daniel Rubery <drubery@chromium.org>
Commit-Queue: Xinghui Lu <xinghuilu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1209592}