[Win7,Full-screen] Outstanding issues in 32-bit mode

[tomcw]

Full screen issues: (Win7, VAIO)

• Screen not redrawn after:
  • Switching to Fullscreen mode
  • Switching mode (F9/Shift+F9)
  • Bringing up a dialog (Config or Open Disk Image)
  • NB. debugger on/off correctly forces a redraw
  • Also see my comment in: ScreenWindowResize()
  • These redraw issues don't occur in 8-bit FS mode. NB. The green drive activity "1" and capslock "A" are not erased when a dialog is passed over them.
• There's noticable flicker when blanking out alt lines (50% mode).
  • Consider doing this 50% operation in CopySource() instead
• Pause -> Unpause: not completely undrawn correctly (in lower-right corner)

[tomcw]

Fixed fullscreen flicker (in 50% mode): 99bed3ed36fb3488a23161188a2e97bcf775c3e6

Tested on Win7 only:

• Tested PrintScreen with/without SHIFT modifier.
• Tested all screen modes (in both Windowed & Fullscreen mode)