fixed another validity checking in external parsed entities raised by

* xmlreader.c python/tests/reader2.py: fixed another validity
  checking in external parsed entities raised by Stéphane Bidoul
  and added a specific regression test.
* python/tests/reader3.py: cleanup
Daniel
diff --git a/xmlreader.c b/xmlreader.c
index 7c04a0e..fea78cb 100644
--- a/xmlreader.c
+++ b/xmlreader.c
@@ -151,7 +151,8 @@
 				 ctxt->myDoc, ctxt->node, fullname);
 	}
     }
-    reader->state = XML_TEXTREADER_ELEMENT;
+    if (reader != NULL)
+	reader->state = XML_TEXTREADER_ELEMENT;
 }
 
 /**
@@ -184,10 +185,12 @@
 		                ctxt->myDoc, node, fullname);
 	}
     }
-    if (reader->state == XML_TEXTREADER_ELEMENT)
-	reader->wasempty = 1;
-    else
-	reader->wasempty = 0;
+    if (reader != NULL) {
+	if (reader->state == XML_TEXTREADER_ELEMENT)
+	    reader->wasempty = 1;
+	else
+	    reader->wasempty = 0;
+    }
 }
 
 /**