Include wx/app.h according to precompiled headers of wx/wx.h (with other minor cleaning).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@38945 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/db.cpp

@@ -35,6 +35,7 @@
     #include "wx/string.h"
     #include "wx/utils.h"
     #include "wx/log.h"
+    #include "wx/app.h"
 #endif
 
 #ifdef DBDEBUG_CONSOLE
@@ -53,7 +54,6 @@
 #include "wx/db.h"
 
 // DLL options compatibility check:
-#include "wx/app.h"
 WX_CHECK_BUILD_OPTIONS("wxODBC")
 
 WXDLLIMPEXP_DATA_ODBC(wxDbList*) PtrBegDbList = 0;