Replace ConsumeNumberRaw with ConsumeNumber for cubic-bezier()

We still don't support element-dependent arguments, but add a test and a
comment in the code.

Bug: 407420298
Change-Id: If1e802bcdc0c868ab4c7edd4231900c94f7275b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6415890
Reviewed-by: Daniil Sakhapov <[email protected]>
Commit-Queue: Rune Lillesveen <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1440211}

Author: lilles

css/css-easing/timing-functions-syntax-valid.html

@@ -21,6 +21,7 @@
 test_valid_value("animation-timing-function", "cubic-bezier(0, -2, 1, 3)");
 test_valid_value("animation-timing-function", "cubic-bezier(0, 0.7, 1, 1.3)");
 test_valid_value("animation-timing-function", "cubic-bezier(calc(-2), calc(0.7 / 2), calc(1.5), calc(0))", "cubic-bezier(calc(-2), calc(0.35), calc(1.5), calc(0))");
+test_valid_value("animation-timing-function", "cubic-bezier(0, sibling-index(), 1, sign(2em - 20px))");
 
 test_valid_value("animation-timing-function", "steps(4, start)");
 test_valid_value("animation-timing-function", "steps(2, end)", "steps(2)");