Fix SkVertices serialization bug. Also remove Builder getters for counts.

We already checked the SkSafeRange earlier (after its last use). Here we
need to be checking the SkSafeMath object. Oops.

The counts are directly copied from the constructor to the vertices'
fields - the user already knows what they are (and the tests are
verifying a tautology).

Bug: skia:9984
Change-Id: I33c62e02825718e497834b0dfa40d0d56e46a197
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/280963
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Reed <reed@google.com>
3 files changed