don't crash if the grid is being deleted while a cell editor is still shown (closes #9991)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@55798 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/grid.cpp

@@ -4315,6 +4315,11 @@ bool wxGrid::Create(wxWindow *parent, wxWindowID id,
 
 wxGrid::~wxGrid()
 {
+    // Ensure that the editor control is destroyed before the grid is,
+    // otherwise we crash later when the editor tries to do something with the
+    // half destroyed grid
+    HideCellEditControl();
+
     // Must do this or ~wxScrollHelper will pop the wrong event handler
     SetTargetWindow(this);
     ClearAttrCache();