[Code Health] Remove the WebFont.HttpCacheStatus histogram

OBSOLETE_HISTOGRAM[WebFont.HttpCacheStatus]=Expired in 2021

This change removes the code that records WebFont.HttpCacheStatus*
histograms, as well as relevant tests and the histogram itself.

Bug: 1384976
Change-Id: Ib7a9535794f2896cabe649c5402a75f0986155c7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4549343


Reviewed-by: Luc Nguyen <lucnguyen@google.com>
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Yao Xiao <yaoxia@chromium.org>
Reviewed-by: Shivani Sharma <shivanisha@chromium.org>
Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1148544}