Remove CEF warnings about unused features and snake case names.

ports/cef/lib.rs

@@ -4,7 +4,6 @@
 
 #![feature(borrow_state)]
 #![feature(box_syntax)]
-#![feature(convert)]
 #![feature(core_intrinsics)]
 #![feature(filling_drop)]
 #![feature(iter_arith)]

ports/cef/stubs.rs

@@ -9,6 +9,7 @@
 macro_rules! stub(
     ($name:ident) => (
         #[no_mangle]
+        #[allow(non_snake_case)]
         pub extern "C" fn $name() {
             println!("CEF stub function called: {}", stringify!($name));
             unsafe {