MDL-9866 reverting previous incorrect fix for include() in simpletest library; patching grade unit tests instead

lib/simpletestlib/readme_moodle.txt

@@ -1,7 +1,7 @@
 Description of Simpletest 1.0.1beta library import into Moodle
 
 Changes:
- * test_case.php - include() changed to include_once() in _requireWithError() MDL-9866
+ * none
 
 skodak
 

lib/simpletestlib/test_case.php

@@ -458,7 +458,7 @@
          */
         function _requireWithError($file) {
             $this->_enableErrorReporting();
-            include_once($file); // moodle change - include prevents inheritance of test classes MDL-9866
+            include($file);
             $error = isset($php_errormsg) ? $php_errormsg : false;
             $this->_disableErrorReporting();
             $self_inflicted_errors = array(