Remove duplicated GetTextPeer() definitions from derived classes.

GetTextPeer() may be implemented directly in wxTextEntry under OS X, there is
no need to define it (identically) in wxTextCtrl and wxComboBox.

Also just call this method instead of duplicating its code in wxOSX
wxTextCtrl.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@63878 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/osx/combobox.h

@@ -146,10 +146,6 @@ class WXDLLIMPEXP_CORE wxComboBox : public wxControl, public wxComboBoxBase
     WX_DECLARE_CONTROL_CONTAINER();
 #endif
 
-    // only used by the native Cocoa combobox, but we must define it everywhere
-    // to maintain the wxTextEntry abstraction.
-    virtual wxTextWidgetImpl * GetTextPeer() const;
-
 #if wxOSX_USE_COCOA
     wxComboWidgetImpl* GetComboPeer() const;
 #endif