Make AsyncExecLoopExitEnum enum in the wxExecute() test public.

This fixes VC6 build as the nested class couldn't access a private enum inside
the enclosing class.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74354 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/exec/exec.cpp

@@ -49,6 +49,15 @@
 
 #define SLEEP_END_STRING "Done sleeping"
 
+namespace
+{
+    enum AsyncExecLoopExitEnum
+    {
+        AsyncExec_DontExitLoop,
+        AsyncExec_ExitLoop
+    };
+} // anonymous namespace
+
 // ----------------------------------------------------------------------------
 // test class
 // ----------------------------------------------------------------------------
@@ -94,12 +103,6 @@ private:
                              CheckStream check,
                              const char* expectedContaining);
 
-    enum AsyncExecLoopExitEnum
-    {
-        AsyncExec_DontExitLoop,
-        AsyncExec_ExitLoop
-    };
-
     // This class is used as a helper in order to run wxExecute(ASYNC)
     // inside of an event loop.
     class AsyncInEventLoop : public wxTimer