Revert "Remove (unnecessary?) flush in RenderYUVAToRGBA"

This reverts commit 49b293a7d587fd91f8e0e00c5cb96d36b5968804.

Reason for revert: speculative to fix chrome roll

Original change's description:
> Remove (unnecessary?) flush in RenderYUVAToRGBA
> 
> I don't think we need a flush here.
> 
> Change-Id: I87bf41b491835578e7df9bea4e15ea24dd551c1e
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/196645
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Robert Phillips <robertphillips@google.com>

TBR=egdaniel@google.com,jvanverth@google.com,robertphillips@google.com

Change-Id: I49305a5a2bcd5fe112b5f55b64511fd05d6c8548
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/197305
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
1 file changed