 event is not leaked into the
      // ancestor tree, so we must do this manually.
      // See https://w3c.github.io/webcomponents/spec/shadow/#events-that-are-not-leaked-into-ancestor-trees.
      if (this.shadowRoot) {
        this.fire(event.type, {sourceEvent: event}, {
          node: this,
          bubbles: event.bubbles,
          cancelable: event.cancelable
        });
      }
    }
  };

  /** @polymerBehavior */
  Polymer.PaperInputBehavior = [
    Polymer.IronControlState,
    Polymer.IronA11y