Push back expiration of histograms related to FontSize

We still intend to use these histograms for analysis. Looks like I was
a little too ambitious with how long it would take to be done with these.

Bug: 915890
Change-Id: Iebbd33fb9bc7fc0df698abe431e9dde7e45f190b
Reviewed-on: https://chromium-review.googlesource.com/c/1393891
Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Daniel Rubery <drubery@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619811}
1 file changed