Reland "Update fontconfig cache key handling"

This is a reland of eb686109386934e0ced433a64f1e6704afc613ab

Reland changes: Remove stale ".uuid" output file from BUILD.gn.

Original change's description:
> Update fontconfig cache key handling
>
> Since If6853404f1e87de4f95a24f6231282543814bd63, the "uuid" variable has
> been referring to the MD5 of a fixed string. Update the comment as such,
> and remove the now-unneeded .uuid file writing.
>
> Also update test_fonts/README.chromium as the manual UUID change is no
> longer necessary or effective.
>
> Bug: 767754
> Change-Id: I07a9b10a631e755877cbcb7df40a53359329f8a3
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2209397
> Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
> Auto-Submit: Timothy Gu <timothygu@chromium.org>
> Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#770287}

Bug: 767754
Change-Id: I6ec0ad451e9e84e1d42060df658dd49494227edb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2209760
Commit-Queue: Timothy Gu <timothygu@chromium.org>
Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Dominik Röttsches <drott@chromium.org>
Cr-Commit-Position: refs/heads/master@{#770666}
NOKEYCHECK=True
GitOrigin-RevId: eeb70ead49438ebb30ce3de7903dc8ac4912d71f
1 file changed