DevTools: Show asynchronous call stacks on frontend.

Source/devtools/front_end/Settings.js

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 99 matching lines @@
     this.splitVerticallyWhenDockedToRight = this.createSetting("splitVerticallyWhenDockedToRight", true);
     this.visiblePanels = this.createSetting("visiblePanels", {});
     this.shortcutPanelSwitch = this.createSetting("shortcutPanelSwitch", false);
     this.showWhitespacesInEditor = this.createSetting("showWhitespacesInEditor", false);
     this.skipStackFramesSwitch = this.createSetting("skipStackFramesSwitch", false);
     this.skipStackFramesPattern = this.createSetting("skipStackFramesPattern", "");
     this.screencastEnabled = this.createSetting("screencastEnabled", false);
     this.screencastSidebarWidth = this.createSetting("screencastSidebarWidth", 300);
     this.showEmulationViewInDrawer = this.createSetting("showEmulationViewInDrawer", true);
     this.showRenderingViewInDrawer = this.createSetting("showRenderingViewInDrawer", true);
+    this.enableAsyncStackTraces = this.createSetting("enableAsyncStackTraces", false);
+    this.maxAsyncStackTraceDepth = this.createSetting("maxAsyncStackTraceDepth", 4);
 }
 
 WebInspector.Settings.prototype = {
     /**
      * @param {string} key
      * @param {*} defaultValue
      * @return {!WebInspector.Setting}
      */
     createSetting: function(key, defaultValue)
     {
@@ skipping 340 matching lines @@
     {
         // If there are too many breakpoints in a storage, it is likely due to a recent bug that caused
         // periodical breakpoints duplication leading to inspector slowness.
         if (breakpointsSetting.get().length > maxBreakpointsCount)
             breakpointsSetting.set([]);
     }
 }
 
 WebInspector.settings = new WebInspector.Settings();
 WebInspector.experimentsSettings = new WebInspector.ExperimentsSettings();