Ignore extra modify events after rename in wxFileSystemWatcher.

Document that such extra events may occur and generally improve the event
types documentation.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70074 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/fswatcher/fswatchertest.cpp

@@ -348,6 +348,21 @@ public:
         CPPUNIT_ASSERT_EQUAL(expected.GetPath(), e->GetPath());
         CPPUNIT_ASSERT_EQUAL(expected.GetNewPath(), e->GetNewPath());
 
+        // Under MSW extra modification events are sometimes reported after a
+        // rename and we just can't get rid of them, so ignore them in this
+        // test if they do happen.
+        if ( e->GetChangeType() == wxFSW_EVENT_RENAME &&
+                m_events.size() == 2 )
+        {
+            const wxFileSystemWatcherEvent* const e2 = m_events.back();
+            if ( e2->GetChangeType() == wxFSW_EVENT_MODIFY &&
+                    e2->GetPath() == e->GetNewPath() )
+            {
+                // This is a modify event for the new file, ignore it.
+                return;
+            }
+        }
+
         WX_ASSERT_EQUAL_MESSAGE
         (
             (