Add wxOVERRIDE to test files

And cleanup some tailing spaces and tabs.

tests/events/propagation.cpp

@@ -234,8 +234,8 @@ class EventPropagationTestCase : public CppUnit::TestCase
 public:
     EventPropagationTestCase() {}
 
-    virtual void setUp();
-    virtual void tearDown();
+    virtual void setUp() wxOVERRIDE;
+    virtual void tearDown() wxOVERRIDE;
 
 private:
     CPPUNIT_TEST_SUITE( EventPropagationTestCase );