merge_pr_51481

Fix the background color animation between color spaces. srgb and oklch are not behaving correctly.

This CL fixes when background-color and the one in keyframes is
no-legacy and legacy color space mixed, they will end-up been
interpolate as oklab with sRGBLegacy.

In particular oklch(45% 0.2 264) is treated as non-legacy so has been
converted into oklab(45% -0.02 -0.2), but the original
background-color is in hex format, will keep as is(sRGBLegacy), and
These two colors are blending with sRGBLegacy mode; that is why we only
see r component is changing, the other two components are always 0 in
devtools, because they are mixing togather with different expectations.
One want to interpolate with oklab but the other want to interpolate
with sRGB.

Bug: 341132088
Change-Id: Ic0d72f2189b71a22d8f33104e486c868c8af849e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6354303
Commit-Queue: Jason Leo [email protected]
Reviewed-by: Aaron Krajeski [email protected]
Reviewed-by: Kevin Ellis [email protected]
Auto-Submit: Jason Leo [email protected]
Cr-Commit-Position: refs/heads/main@{#1435188}