Some dirty bits need to run before the render pass starts.  An upcoming
change for example needs to break the render pass when the program
pipeline is changed while transform feedback is active.  Another
upcoming change may need to do the same based on a preceding
glMemoryBarrier.

This change adds a new dirty bit to start the render pass after some
dirty bits have already been processed.

Bug: angleproject:5528
Change-Id: I993c9efefed4c8fee268b218a8dd66a582d4e7cd
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2678863
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>