Return after activating already opened document in wxDocManager.

Add accidentally omitted "return" in wxDocManager::CreateDocument() to prevent
recreating already opened documents.

Closes #12277.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65126 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/docview.cpp

@@ -1408,6 +1408,7 @@ wxDocument *wxDocManager::CreateDocument(const wxString& pathOrig, long flags)
             {
                 // file already open, just activate it and return
                 ActivateDocument(doc);
+                return doc;
             }
         }
     }