Win32: Fix a bug in fullscreen. Consolidate the fullscreen code into one function. 99% of the code is the same anyway.
Typo fix.
Should probably be using goingFullscreen too, just for consistency.
Remove unused parameter.
Merge pull request #6566 from thedax/win32-fullscr-fix

Win32: Fix a bug in fullscreen, and consolidate the fullscreen code into one function.