fix for GrVkGpu not always unreffing all command pools

Bug: skia:
Change-Id: I2a122aa25f5a8bedb413b2dca3b53637f8ddd604
Reviewed-on: https://skia-review.googlesource.com/c/176975
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
1 file changed