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

include/wx/osx/dataview.h

@@ -397,7 +397,7 @@ public:
     virtual int GetMaxWidth() const { return m_maxWidth; }
     virtual int GetMinWidth() const { return m_minWidth; }
     virtual wxString GetTitle() const { return m_title; }
-    virtual int GetWidth() const { return m_width; }
+    virtual int GetWidth() const;
     virtual bool IsHidden() const { return false; } // TODO
     virtual bool IsSortOrderAscending() const { return m_ascending; }
     virtual bool IsSortKey() const;
@@ -423,6 +423,10 @@ public:
     }
 
     void SetNativeData(wxDataViewColumnNativeData* newNativeDataPtr); // class takes ownership of pointer
+    int GetWidthVariable() const
+    {
+        return m_width;
+    }
     void SetWidthVariable(int NewWidth)
     {
         m_width = NewWidth;