Remove workaround for not executing no op discard OpsTask.
Remove workaround for not executing no op discard OpsTask.

This should fix the Vulkan validation warnings about have a render pass
with a 0 area bounds.

There are times in Skia (when not doing reduced op list splitting),
where we get a new offscreen surface, discard it, then get a second
offscreen before submitting any draws to the first yet. This causes us to
have an OpsTask for the first with a discard load but no ops. When we
get back to this first surface to add real ops it will have a load load.
Correctness wise we could drop the first OpsTask since it doesn't have
any affect (what the validation warning in this bug is referring to).

This original workaround was there to appease a different vulkan
validation warning about loading unitialized memory at the start of a
render pass. If we drop the discard then the validation would complain
the load (on the second OpsTask) was happening on unitialized memory.
However, with the workaround removed I no longer am getting such a
warning both with and without reducedOpListSplitting. So either we are
now avoiding this case via something else higher up or maybe this warning
was removed from the validation. Or I just can't get a good test case
for it. It does not repro running Skia gm or tests, or running chromes
test case for the 0 area render pass bounds.

Bug: chromium:1279794
Change-Id: I11ad5ce4e0000da74805a4cd9a0a9207d5adf60a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/484562
Auto-Submit: Greg Daniel <39df0a804564ccb6cf75f18db79653821f37c1c5@google.com>
Reviewed-by: Robert Phillips <95e8ac5504948c7bf91b22c16a8dbb7ae7c66bfd@google.com>
Commit-Queue: Robert Phillips <95e8ac5504948c7bf91b22c16a8dbb7ae7c66bfd@google.com>

aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,google/skia,google/skia,aosp-mirror/platform_external_skia,google/skia,google/skia,google/skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia