Make tidy aware of Rust multiline strings

As a result of tighter and more correct handling of character
literals, this now catches a few kinds of syntax involving lifetimes
that were previously missed, so those have been updated.

components/layout/persistent_list.rs

@@ -69,7 +69,7 @@ impl<T> Clone for PersistentList<T> where T: Send + Sync {
     }
 }
 
-pub struct PersistentListIterator<'a,T> where T: 'a + Send + Sync {
+pub struct PersistentListIterator<'a, T> where T: 'a + Send + Sync {
     entry: Option<&'a PersistentListEntry<T>>,
 }