A previous change [1] made FramebufferVk::syncState update scissor and
rasterization samples only when the DRAW framebuffer is synced.  This is
incorrect as the READ framebuffer is synced before the DRAW framebuffer,
and if the two are the same, the latter is discarded.

Very few functions sync both READ and DRAW framebuffers when they are
identical.  A test is tailored to expose this bug.

[1]: https://chromium-review.googlesource.com/c/angle/angle/+/2510013

Bug: angleproject:4988
Change-Id: I6123ac18dded938171bc90a04d4d81f1b42a1694
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2515742
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>