In some state change scenarios the driver uniforms would be updated but
not reapplied to the current state. Fix this by setting the descriptor
sets dirty when we dirty the driver uniforms.

Includes a test using gl_DepthRange. Also fixes a bug with the upcoming
line segment rasterization emulation.

Bug: angleproject:2598
Bug: angleproject:2845
Change-Id: Ia66f3c86f9770ceb145069eec879fd8725111a76
Reviewed-on: https://chromium-review.googlesource.com/1240413Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>