[DevTools] Show an empty Manifest view if no manifest

third_party/WebKit/Source/devtools/front_end/resources/AppManifestView.js

 // Copyright (c) 2016 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.
-/**
- * @implements {SDK.TargetManager.Observer}
- * @unrestricted
- */
 Resources.AppManifestView = class extends UI.VBox {
   constructor() {
     super(true);
     this.registerRequiredCSS('resources/appManifestView.css');
 
     this._reportView = new UI.ReportView(Common.UIString('App Manifest'));
     this._reportView.show(this.contentElement);
 
     this._errorsSection = this._reportView.appendSection(Common.UIString('Errors and warnings'));
     this._identitySection = this._reportView.appendSection(Common.UIString('Identity'));
@@ skipping 15 matching lines @@
     var themeColorField = this._presentationSection.appendField(Common.UIString('Theme color'));
     this._themeColorSwatch = InlineEditor.ColorSwatch.create();
     themeColorField.appendChild(this._themeColorSwatch);
 
     var backgroundColorField = this._presentationSection.appendField(Common.UIString('Background color'));
     this._backgroundColorSwatch = InlineEditor.ColorSwatch.create();
     backgroundColorField.appendChild(this._backgroundColorSwatch);
 
     this._orientationField = this._presentationSection.appendField(Common.UIString('Orientation'));
     this._displayField = this._presentationSection.appendField(Common.UIString('Display'));
-
-    SDK.targetManager.observeTargets(this, SDK.Target.Capability.DOM);
   }
 
   /**
-   * @override
-   * @param {!SDK.Target} target
-   */
-  targetAdded(target) {
-    if (this._resourceTreeModel)
-      return;
-    var resourceTreeModel = SDK.ResourceTreeModel.fromTarget(target);
-    if (!resourceTreeModel)
-      return;
-    this._resourceTreeModel = resourceTreeModel;
-    this._updateManifest();
-    resourceTreeModel.addEventListener(SDK.ResourceTreeModel.Events.MainFrameNavigated, this._updateManifest, this);
-  }
-
-  /**
-   * @override
-   * @param {!SDK.Target} target
-   */
-  targetRemoved(target) {
-    var resourceTreeModel = SDK.ResourceTreeModel.fromTarget(target);
-    if (!this._resourceTreeModel || this._resourceTreeModel !== resourceTreeModel)
-      return;
-    resourceTreeModel.removeEventListener(SDK.ResourceTreeModel.Events.MainFrameNavigated, this._updateManifest, this);
-    delete this._resourceTreeModel;
-  }
-
-  _updateManifest() {
-    this._resourceTreeModel.fetchAppManifest(this._renderManifest.bind(this));
-  }
-
-  /**
    * @param {string} url
    * @param {?string} data
    * @param {!Array<!Protocol.Page.AppManifestError>} errors
    */
-  _renderManifest(url, data, errors) {
-    this._reportView.setURL(Components.Linkifier.linkifyURL(url));
+  renderManifest(url, data, errors) {
+    // This needs to run after the Linkifier listener processes target added event
+    setTimeout(() => this._reportView.setURL(Components.Linkifier.linkifyURL(url)));

[pfeldman, 2017/02/07 00:25:35]

That's a bad assumption to make.

[eostroukhov, 2017/02/07 01:40:38]

I do not see a cleaner option atm. Note - this is not a regression, the issue
had been here for awhile.

     this._errorsSection.clearContent();
     this._errorsSection.element.classList.toggle('hidden', !errors.length);
     for (var error of errors) {
       this._errorsSection.appendRow().appendChild(
           UI.createLabel(error.message, error.critical ? 'smallicon-error' : 'smallicon-warning'));
     }
 
     if (!data)
       data = '{}';
 
@@ skipping 45 matching lines @@
    * @param {!Common.Event} event
    */
   _addToHomescreen(event) {
     var target = SDK.targetManager.mainTarget();
     if (target && target.hasBrowserCapability()) {
       target.pageAgent().requestAppBanner();
       Common.console.show();
     }
   }
 };