Exception when modifying a deleted file type

reactos-bootcd-0.4.15-dev-6955-gdb219e4-x86-gcc-lin-dbg

• Open File extension settings
• Add a new extention (eg : "blabla")
• Give it focus
• Delete it
• It is still displayed on the lower part of the dialog : CORE-19325
• Click on advanced
• Do change and try to close the window : Does not close and logs as below
• Expected result : No exception (advanced button without action if no list item selection)

err:(win32ss/user/user32/windows/message.c:1556) Exception Dialog unicode 7AFA85AA Msg 273 pti B7EAB038 Wndpti B7EAB038 

Guilty code : dll/win32/shell32/dialogs/filetypes.cpp where NULL is passed as edittype.pEntry then used by the Edit window without proper checks here : https://git.reactos.org/?p=reactos.git;a=blob;f=dll/win32/shell32/dialogs/filetypes.cpp;hb=ee11747527d0a4ffff60f5d0b1ee820001ac9319#l1227 assuming pEditType is non-NULL

Patch : filetypes.patch