Put the tests in element.rs into a module block.

src/element.rs

@@ -926,6 +926,9 @@ impl ElementBuilder {
 }
 
 #[cfg(test)]
+mod tests {
+    use super::*;
+
     #[test]
     fn test_element_new() {
         use std::iter::FromIterator;
@@ -1003,3 +1006,4 @@ fn does_not_unescape_cdata() {
         let elem = Element::from_reader(&mut reader).unwrap();
         assert_eq!(elem.text(), "&apos;&gt;blah<blah>");
     }
+}