Fix buffer size assertion in Vulkan

Bug: skia:
Change-Id: I2b878ec288b6dac891fc3724678a528d2db08b09
Reviewed-on: https://skia-review.googlesource.com/93362
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
1 file changed