implement wxLoadedDLL, a safer alternative to wxDL_GET_LOADED (closes #10208)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57405 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/app.cpp

@@ -917,10 +917,7 @@ int wxApp::GetComCtl32Version()
         // depending on the OS version and the presence of the manifest, it can
         // be either v5 or v6 and instead of trying to guess it just get the
         // handle of the already loaded version
-        wxDynamicLibrary dllComCtl32(_T("comctl32.dll"),
-                                     wxDL_VERBATIM |
-                                     wxDL_QUIET |
-                                     wxDL_GET_LOADED);
+        wxLoadedDLL dllComCtl32(_T("comctl32.dll"));
         if ( !dllComCtl32.IsLoaded() )
         {
             s_verComCtl32 = 0;
@@ -958,9 +955,6 @@ int wxApp::GetComCtl32Version()
                 }
             }
         }
-
-        // we shouldn't unload it here as we didn't really load it above
-        dllComCtl32.Detach();
     }
 
     return s_verComCtl32;