This code was not using typeName() to emit its types, inadvertently
generating Metal code containing the `half` type.
We didn't have any unit tests which synthesized a matrix-construct
helper with half types, so Matrices.sksl was cloned into two separate
test files--MatricesFloat and MatricesHalf. These should be equivalent
except for float vs half types.
Change-Id: I19ecea994b8bc45594bb3f69e596896a3bcefe4d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/348180
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
