Delete pending objects before destroying wxConfig during cleanup.

This allows these objects to save their state in wxConfig, as e.g. top level
windows using wxPersistenceManager do.

Closes #16397.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77652 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/appbase.cpp

@@ -281,6 +281,10 @@ void wxAppConsoleBase::OnLaunched()
 
 int wxAppConsoleBase::OnExit()
 {
+    // Delete all pending objects first, they might use wxConfig to save their
+    // state during their destruction.
+    DeletePendingObjects();
+
 #if wxUSE_CONFIG
     // delete the config object if any (don't use Get() here, but Set()
     // because Get() could create a new config object)

src/common/appcmn.cpp

@@ -129,7 +129,10 @@ wxAppBase::~wxAppBase()
 
 void wxAppBase::CleanUp()
 {
-    // clean up all the pending objects
+    // Clean up any still pending objects. Normally there shouldn't any as we
+    // already do this in OnExit(), but this could happen if the user code has
+    // somehow managed to create more of them since then or just forgot to call
+    // the base class OnExit().
     DeletePendingObjects();
 
     // and any remaining TLWs (they remove themselves from wxTopLevelWindows