In Vulkan make sure resolve is sent to GPU when preparing msaa RenderTarget for external IO

In GrDrawingManager, when preparing for I/O we first flush the GPU then call resolve. However,
in Vulkan the resolve lives in a command buffer that needs to be flushed to the GPU as well.

This is most likely the cause we were seeing in Viewer app where first frame was always black
since the actually resolve command buffer was not flushed to the gpu before presenting. All
future frames would then typically show one frame behind.

BUG=skia:

Change-Id: Iaf492f88680b998be0087637279cc78d5a38ec50
Reviewed-on: https://skia-review.googlesource.com/8903
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

0 files changed, 0 insertions, 0 deletions