Fix several build errors in WXQT

Move declaration of wxOwnerDrawnBase::ms_defaultMargin to correct file.
Do not include headers when wxUSE_UIACTIONSIMULATOR is disabled.
Add guards for wxUSE_DRAG_AND_DROP.
Use a different wxFont constructor in printing sample, which is also available in WXQT.

src/qt/uiaction.cpp

@@ -12,6 +12,8 @@
     #pragma hdrstop
 #endif
 
+#if wxUSE_UIACTIONSIMULATOR
+
 #include "wx/uiaction.h"
 #include "wx/private/uiaction.h"
 
@@ -24,8 +26,6 @@
 #include "wx/qt/private/converter.h"
 
 
-#if wxUSE_UIACTIONSIMULATOR
-
 using namespace Qt;
 using namespace QTest;