First steps of &JSRef -> JSRef conversion

Replace &JSRef with JSRef in the bulk of the generated code. This will
remove a level of indirection throughout all DOM code.

This patch doesn't change methods implemented on JSRef<T> to take `self`
rather than `&self`, and it leaves a few other uses of &JSRef, but those
changes can be made incrementally.

components/script/dom/domrect.rs

@@ -32,11 +32,11 @@ impl DOMRect {
         }
     }
 
-    pub fn new(window: &JSRef<Window>,
+    pub fn new(window: JSRef<Window>,
                top: Au, bottom: Au,
                left: Au, right: Au) -> Temporary<DOMRect> {
         reflect_dom_object(box DOMRect::new_inherited(top, bottom, left, right),
-                           &Window(*window), DOMRectBinding::Wrap)
+                           &Window(window), DOMRectBinding::Wrap)
     }
 }