merge_pr_48998

Add WebDX mapping and WPT test mapping for forced-colors

Change-Id: I5d1d3136bc96f870fd3730ce5291e7eb8402b60d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5993499
Commit-Queue: Steinar H Gunderson [email protected]
Reviewed-by: Shunya Shishido [email protected]
Reviewed-by: Rune Lillesveen [email protected]
Cr-Commit-Position: refs/heads/main@{#1378917}