Fix string leaking (and destructors not getting called) when there are XMLNodes that aren't in the document tree

xmltest.cpp

@@ -1641,6 +1641,20 @@ int main( int argc, const char ** argv )
 		}
 	}
 
+	{
+		// Oh those memory leaks.
+		// Only way to see these is in the (Windows) allocator tracking.
+		{
+			XMLDocument doc;
+			doc.NewElement("LEAK 1");
+		}
+		{
+			XMLDocument doc;
+			XMLElement* ele = doc.NewElement("LEAK 2");
+			doc.DeleteNode(ele);
+		}
+	}
+
     // ----------- Line Number Tracking --------------
     {
         struct TestUtil: XMLVisitor