Match latest variant spec; update hue rotation logic

- Update a couple rotations to match spec (ex. rotation occurs at 151
degrees instead of 141)
- If hue rotation specs have an entry at 0 degrees, they also need an
entry at 360 degrees. There's no way to determine that, for example,
321 is between 315 and 0, 360 must be listed.
- Find hue rotation in a way that ensures ex. an angle isn't tested for
being between 0 and 360 degrees, as that will always return true.
Instead, use first element, (always 0 degrees), check if angle is
between and the next element, and stop once the next element is 360
degrees (always the last element in the array)
- Remove code that became unused after the above change.

Test: atest ColorSchemeTest (unit test); atest SystemPaletteTest (CTS).
Spent ~4 hours trying a variety of wallpapers, and seed colors, and
used dumpsys to verify results match UX spec. Create spreadsheet for UX
to fill out their spec, then another spreadsheet that contains the
dumpsys results for blue/red/yellow/green seed colors across all theme
variants, and the preset colors for Ice Cream and Fruit Salad variants.
Confirmed the runtime results, as reported by dumpsys, match the spec
in all cases.
Bug: 213314628
Change-Id: Id35faa294bf82c0e81c2690c65c42218a87c236a