DevTools: allow reattaching main target live.

third_party/WebKit/Source/devtools/front_end/sdk/TargetManager.js

 /*
  * Copyright 2014 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /**
  * @constructor
  * @extends {WebInspector.Object}
  */
@@ skipping 217 matching lines @@
         if (target.hasBrowserCapability()) {
             target.subTargetsManager = new WebInspector.SubTargetsManager(target);
             target.serviceWorkerManager = new WebInspector.ServiceWorkerManager(target, target.subTargetsManager);
         }
 
         this.addTarget(target);
         return target;
     },
 
     /**
+     * @param {function()} factory
+     */
+    setMainTargetFactory: function(factory)
+    {
+        this._mainTargetFactory = factory;
+    },
+
+    /**
+     * @param {function(string)} dispatch
+     * @return {!Promise<!WebInspector.RawProtocolConnection>}
+     */
+    interceptMainConnection: function(dispatch)

[dgozman, 2016/10/15 00:26:26]

Let's rework TargetDisposed event.

+    {
+        var targets = this._targets.slice();
+        for (var i = targets.length - 1; i >=0 ; --i)
+            targets[i].connection().close();
+
+        var yeld = InspectorFrontendHost.reattach.bind(InspectorFrontendHost, this._mainTargetFactory);

[dgozman, 2016/10/15 00:26:26]

yield

+
+        var fulfill;
+        var result = new Promise(resolve => fulfill = resolve);
+        InspectorFrontendHost.reattach(() => fulfill(new WebInspector.RawProtocolConnection(dispatch, yeld)));
+        return result;
+    },
+
+    /**
      * @param {!WebInspector.Target} target
      * @return {!Array<!WebInspector.TargetManager.Observer>}
      */
     _observersForTarget: function(target)
     {
         return this._observers.filter((observer) => target.hasAllCapabilities(observer[this._observerCapabiliesMaskSymbol] || 0));
     },
 
     /**
      * @param {!WebInspector.Target} target
@@ skipping 33 matching lines @@
         {
             return resourceTreeModel.addEventListener(sourceEvent, this._redispatchEvent.bind(this, targetEvent));
         }
     },
 
     /**
      * @param {!WebInspector.Target} target
      */
     removeTarget: function(target)
     {
+        if (!this._targets.includes(target))

[dgozman, 2016/10/15 00:26:26]

Let's try to only remove main.

+            return;
         this._targets.remove(target);
         var resourceTreeModel = WebInspector.ResourceTreeModel.fromTarget(target);
         var treeModelListeners = resourceTreeModel && resourceTreeModel[WebInspector.TargetManager._listenersSymbol];
         if (treeModelListeners)
             WebInspector.EventTarget.removeEventListeners(treeModelListeners);
 
         var copy = this._observersForTarget(target);
         for (var i = 0; i < copy.length; ++i)
             copy[i].targetRemoved(target);
 
@@ skipping 88 matching lines @@
     /**
      * @param {!WebInspector.Target} target
      */
     targetRemoved: function(target) { },
 }
 
 /**
  * @type {!WebInspector.TargetManager}
  */
 WebInspector.targetManager = new WebInspector.TargetManager();