Third land of "Restore GL_UNPACK_ROW_LENGTH to 0 between MIP levles"

Fix: Use non-zero rowbytes when uploading zeros for initial texture clear

This reverts commit f16020ba1bc58d3af07f2b4a40ac8bdbd7150ab1.

Bug: chromium:981254
Change-Id: Iafd5893dd1b397ec1d91c64d48d46059e62488a7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/226557
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
4 files changed