Need to ensure that the right background is explicitly set.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@28114 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/calctrl.cpp

@@ -312,7 +312,11 @@ bool wxCalendarCtrl::Create(wxWindow *parent,
     // above it
     SetBestSize(size);
     SetPosition(pos);
-        
+
+    // Since we don't paint the whole background make sure that the platform
+    // will use the right one.
+    SetBackgroundColour(GetBackgroundColour());
+    
     SetHolidayAttrs();
 
     return true;