text: /*
   * Copyright (C) 2014, 2015 Apple Inc. All rights reserved.
   * Copyright (C) 2013, 2014 University of Washington. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  // This class supports adding and removing many listeners at once.
  // Add DOM or Inspector event listeners to the set using `register()`.
  // Use `install()` and `uninstall()` to enable or disable all listeners
  // in the set at once.
  
  WI.EventListenerSet = class EventListenerSet
  {
      constructor(defaultThisObject, name)
      {
          this.name = name;
          this._defaultThisObject = defaultThisObject;
  
          this._listeners = [];
          this._installed = false;
      }
  
      // Public
  
      register(emitter, type, callback, thisObject, usesCapture)
      {
          console.assert(emitter, `Missing event emitter for event: ${type}.`);
          console.assert(type, "Missing event type.");
          console.assert(callback, `Missing callback for event: ${type}.`);
          var emitterIsValid = emitter && (emitter instanceof WI.Object || emitter instanceof Node || (typeof emitter.addEventListener === "function"));
          console.assert(emitterIsValid, "Event emitter ", emitter, ` (type: ${type}) is null or does not implement Node or WI.Object.`);
  
          if (!emitterIsValid || !type || !callback)
              return;
  
          this._listeners.push({listener: new WI.EventListener(thisObject || this._defaultThisObject), emitter, type, callback, usesCapture});
      }
  
      unregister()
      {
          if (this._installed)
              this.uninstall();
          this._listeners = [];
      }
  
      install()
      {
          console.assert(!this._installed, "Already installed listener group: " + this.name);
          if (this._installed)
              return;
  
          this._installed = true;
  
          for (var data of this._listeners)
              data.listener.connect(data.emitter, data.type, data.callback, data.usesCapture);
      }
  
      uninstall(unregisterListeners)
      {
          console.assert(this._installed, "Trying to uninstall listener group " + this.name + ", but it isn't installed.");
          if (!this._installed)
              return;
  
          this._installed = false;
  
          for (var data of this._listeners)
              data.listener.disconnect();
  
          if (unregisterListeners)
              this._listeners = [];
      }
  };
  