URL-encode chars in fragment.

Author: kpreid

library/alloc/src/task.rs

@@ -29,7 +29,7 @@ use crate::sync::Arc;
 ///
 /// <!-- This impl is reachable from `alloc` but rustdoc only lists it in `std`
 ///      because `alloc` doesn't reexport `Waker` -->
-/// [wi]: ../../std/task/struct.Waker.html#impl-From<Arc<W,+Global>>-for-Waker
+/// [wi]: ../../std/task/struct.Waker.html#impl-From%3CArc%3CW,+Global%3E%3E-for-Waker
 ///
 /// # Examples
 ///