added wxTextEntry::SetHint() (a.k.a. cue banner or placeholder string)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@59263 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/combobox.h

@@ -169,6 +169,9 @@ protected:
 
     virtual wxSize DoGetBestSize() const;
 
+    // implement wxTextEntry pure virtual method
+    virtual wxWindow *GetEditableWindow() { return this; }
+
     // Widgets that use the style->base colour for the BG colour should
     // override this and return true.
     virtual bool UseGTKStyleBase() const { return true; }