Vulkan: Fix looped clears. These were broken by command re-ordering. The first problem was that the Framebuffer RenderNode was not correctly being flagged as dirty. This is fixed by keeping a serial instead of a bool to track the RenderNode's cleanliness. The second issue was that an image layout transition was being set with incorrect bits. Fix this by using the correct access mask. This fixes angle_perftests's Vulkan render test. Bug: angleproject:2264 Bug: chromium:798866 Change-Id: I268b0f7aeb2c5e22892f6ef59dec62391b30bfb4 Reviewed-on: https://chromium-review.googlesource.com/848539 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>