auto merge of #3757 : brunoabinader/servo/content_changed, r=jdm

```JSRef<Attr>``` does not require allocating a ```DOMString``` for value, which are unused in most cases. It also provides more access to ```Attr``` data.

1 files changed, 9 insertions, 7 deletions

diff --git a/components/script/dom/htmlbodyelement.rs b/components/script/dom/htmlbodyelement.rs
index 948a7192aa0..4be4c473d01 100644
--- a/components/script/dom/htmlbodyelement.rs
+++ b/components/script/dom/htmlbodyelement.rs
@@ -2,6 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use dom::attr::Attr;
+use dom::attr::AttrHelpers;
 use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::HTMLBodyElementBinding;
 use dom::bindings::codegen::Bindings::HTMLBodyElementBinding::HTMLBodyElementMethods;
@@ -18,7 +20,6 @@ use dom::node::{Node, ElementNodeTypeId, window_from_node};
 use dom::virtualmethods::VirtualMethods;
 
 use servo_util::str::DOMString;
-use string_cache::Atom;
 
 #[dom_struct]
 pub struct HTMLBodyElement {
@@ -63,13 +64,14 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLBodyElement> {
         Some(element as &VirtualMethods)
     }
 
-    fn after_set_attr(&self, name: &Atom, value: DOMString) {
+    fn after_set_attr(&self, attr: JSRef<Attr>) {
         match self.super_type() {
-            Some(ref s) => s.after_set_attr(name, value.clone()),
+            Some(ref s) => s.after_set_attr(attr),
             _ => (),
         }
 
-        if name.as_slice().starts_with("on") {
+        let name = attr.local_name().as_slice();
+        if name.starts_with("on") {
             static forwarded_events: &'static [&'static str] =
                 &["onfocus", "onload", "onscroll", "onafterprint", "onbeforeprint",
                   "onbeforeunload", "onhashchange", "onlanguagechange", "onmessage",
@@ -80,14 +82,14 @@ impl<'a> VirtualMethods for JSRef<'a, HTMLBodyElement> {
                                         window.get_url(),
                                         window.reflector().get_jsobject());
             let evtarget: JSRef<EventTarget> =
-                if forwarded_events.iter().any(|&event| name.as_slice() == event) {
+                if forwarded_events.iter().any(|&event| name == event) {
                     EventTargetCast::from_ref(*window)
                 } else {
                     EventTargetCast::from_ref(*self)
                 };
             evtarget.set_event_handler_uncompiled(cx, url, reflector,
-                                                  name.as_slice().slice_from(2),
-                                                  value);
+                                                  name.slice_from(2),
+                                                  attr.value().as_slice().to_string());
         }
     }
 }