check in the 'selective yield' patch (see ticket #10320):

- implements YieldFor() with event filtering for wxMSW and wxGTK,
  adds TODO markers in other ports;
- replaces wxYield() in GTK's clipboard code with a wxTheApp->YieldFor() call, thus fixing possible reentrancies 
(and modifies clipboard sample to test synchronous IsSupported calls)
- replaces wxYieldIfNeeded() calls in wxProgressDialog with wxTheApp->YieldFor() calls, so that it processes only 
UI/user-input events, thus fixing the race condition visible in the "thread" sample
- documents the new functions


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58654 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/osx/carbon/app.cpp

@@ -1119,7 +1119,7 @@ void wxCYield()
 
 // Yield to other processes
 
-bool wxApp::Yield(bool onlyIfNeeded)
+bool wxApp::DoYield(bool onlyIfNeeded, long eventsToProcess)
 {
 #if wxUSE_THREADS
     // Yielding from a non-gui thread needs to bail out, otherwise we end up
@@ -1141,6 +1141,7 @@ bool wxApp::Yield(bool onlyIfNeeded)
     }
 
     m_isInsideYield = true;
+    m_eventsToProcessInsideYield = eventsToProcess;
 
 #if wxUSE_LOG
     // disable log flushing from here because a call to wxYield() shouldn't