Return the real column width from wxOSX wxDataViewColumn::GetWidth().

Code used to return the last programmatically set width value instead of the
real column width which could have been changed by user if the column was
resizeable, fix this by returning the current NSTableColumn:width value.

Closes #11397.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62516 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/osx/carbon/dataview.cpp

@@ -2476,6 +2476,13 @@ wxDataViewColumn::~wxDataViewColumn()
   delete m_NativeDataPtr;
 }
 
+int wxDataViewColumn::GetWidth() const
+{
+    // FIXME: This returns the last programatically set width and will not work if
+    //        the user changes the column's width by dragging it with the mouse.
+    return m_width;
+}
+
 bool wxDataViewColumn::IsSortKey() const
 {
     wxDataViewCtrl * const dataViewCtrlPtr(GetOwner());