If UtilsVk::clearFramebuffer issues a draw call on the currently open
render pass (as opposed to starting one itself), ContextVk would be
unaware of the fact that the graphics pipeline and descriptor sets have
been changed.

This change sets the necessary dirty bits for ContextVk to recover from
a UtilsVk::clearFramebuffer call.

Bug: chromium:1141040
Change-Id: I865220fb5b3b78bf4c6b6b2896e57d8a7490c270
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2493184
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>