Fix #ifdef for fullscreen toggle.
CGP fixes in D3D9.
Rework to D3D9 aspect ratio handling.
Fix D3D9 viewport when X/Y is < 0.
Verify that RGUI texture is non-zero.

If we're converting, just use ARGB8888 in d3d9.
Avoid complete reinit on apply_state_changes.

Clean up multi-pass logic a bit in D3D9.
Always clear out backbuffer fully.
Fix single pass in D3D9.