docs(guide): improve Protractor test for bindings

This needs Protractor >= 1.3.0 to work.

Author: elgalu

docs/content/guide/directive.ngdoc

@@ -87,8 +87,17 @@ Here are some equivalent examples of elements that match `ngBind`:
   </file>
   <file name="protractor.js" type="protractor">
     it('should show off bindings', function() {
-      expect(element(by.css('div[ng-controller="Controller"] span[ng-bind]')).getText())
-          .toBe('Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)');
+      var containerElm = element(by.css('div[ng-controller="Controller"]'));
+      var nameBindings = containerElm.all(by.binding('name'));
+    
+      expect(nameBindings.count()).toBe(5);
+      expect(nameBindings.getText()).toEqual(
+        [ 'Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)',
+          'Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)',
+          'Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)',
+          'Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)',
+          'Max Karl Ernst Ludwig Planck (April 23, 1858 – October 4, 1947)' ]
+      );
     });
   </file>
 </example>