Remove the apparently unneeded wxPGPropArgCls default ctor.

This ctor didn't initialize the flags correctly and could result in a crash
when a default constructed object was destroyed.

Closes #15174.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73898 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Copy max width of wxGridCellTextEditor when cloning it.

Previously the max number of characters that could be entered into the editor
was lost when it was cloned, making it impossible to really limit the user
entry.

Closes #15175.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73899 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775