/guava/guava-gwt/src-super/com/google/common/collect/super/com/google/common/collect/ImmutableSet.java
return null;
return this;
public Builder<E> addAll(Iterable<? extends E> elements) { if (elements instanceof Collection) { Collection<?> collection = (Collection<?>) elements; contents.ensureCapacity(contents.size() + collection.size()); } super.addAll(elements); <extra_id_0> } @CanIgnoreReturnValue @Override public Builder<E> addAll(Iterator<? extends E> elements) { super.addAll(elements); return this;