GitLab

Divided the rotation tests into two groups: one for common axis,
second for interpolated axis + angle (SLERP).  By separating in this
way, it is easier to match up the tests with the corresponding images.

The 0 -> 90 degree tests for common-axis rotations were changed to
30 -> 90 since a zero degree rotation matches any non-zero counterpart.

Tests added to both groups to verify the following:

* rotation with scaled axis
* rotate -> rotateZ
* special case of a zero rotation angle
* counter-rotation with negative angle
* counter-rotation with inverted axis
* axis+angle interpolation (SLERP)

Bug: 998175, 929841
Change-Id: Iefcfa9bf0d55b6df7f459f51c8b900dd991ab890
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2513796Reviewed-by: Xida Chen <xidachen@chromium.org>
Commit-Queue: Kevin Ellis <kevers@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823746}