CppunitTest_cppcanvas_emfplus: adapt to now enabled sidebar in Draw

Needed since 583e9d834dd795e18e4f8245fc2fe45736607ef9 (Present the
(collapsed) sidebar also in Calc and Draw., 2014-11-22).

Change-Id: I1664b6132ba7ba1e6aee024bd1a12c0ed3086eb0