DevTools: Use JS symbols instead of strings for eligible events.

third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js

 /*
  * Copyright (C) 2007, 2008 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * 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.
@@ skipping 1077 matching lines @@
 WebInspector.ConsoleViewFilter = function(view)
 {
     this._messageURLFiltersSetting = WebInspector.settings.createSetting("messageURLFilters", {});
     this._messageLevelFiltersSetting = WebInspector.settings.createSetting("messageLevelFilters", {});
 
     this._view = view;
     this._messageURLFilters = this._messageURLFiltersSetting.get();
     this._filterChanged = this.dispatchEventToListeners.bind(this, WebInspector.ConsoleViewFilter.Events.FilterChanged);
 };
 
+/** @enum {symbol} */
 WebInspector.ConsoleViewFilter.Events = {
-    FilterChanged: "FilterChanged"
+    FilterChanged: Symbol("FilterChanged")
 };
 
 WebInspector.ConsoleViewFilter.prototype = {
     addFilters: function(filterBar)
     {
         this._textFilterUI = new WebInspector.TextFilterUI(true);
         this._textFilterUI.addEventListener(WebInspector.FilterUI.Events.FilterChanged, this._textFilterChanged, this);
         filterBar.addFilter(this._textFilterUI);
 
         this._hideNetworkMessagesCheckbox = new WebInspector.CheckboxFilterUI("hide-network-messages", WebInspector.UIString("Hide network messages"), true, WebInspector.moduleSetting("hideNetworkMessages"));
@@ skipping 302 matching lines @@
             return true;
         }
         return false;
     }
 }
 
 /**
 * @typedef {{messageIndex: number, matchIndex: number}}
 */
 WebInspector.ConsoleView.RegexMatchRange;