[Bug 52423] GdipDeleteRegion in some cases try to delete NULL elements

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=52423

--- Comment #1 from Konstantin  ---
Unfortunately, the error occurs when working with a heavy WinForms application
under Wine-Mono, an attempt to repeat his behavior in the test example does not
give the desired result. The error itself is randomly apear when the user is
working with forms - editing and copying text.

Detailed testing has shown that the proposed patch does not solve the problem
completely. WINEDEBUG=gdiplus did not give useful information.