/guava/android/guava/src/com/google/common/collect/Synchronized.java
delegate( ).push( e) ;delegate( ).addFirst( e) ;
delegate ( ) .addFirst ( e ) ;
Deque<E> delegate() { return (Deque<E>) super.delegate(); } @Override public void addFirst(E e) { synchronized (mutex) { <extra_id_0> } } @Override public void addLast(E e) { synchronized (mutex) { delegate().addLast(e);