Improve DSL error reporting with invalid array sizes

This eliminates an extra "expected int literal" error when the
array size is an invalid expression.

Change-Id: Iaf5d15316df3ec5200d51d73c14d7e428ce17be9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/443236
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
9 files changed