[DevTools] Make resource tree model optional

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

Index: third_party/WebKit/Source/devtools/front_end/resources/ResourcesPanel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/resources/ResourcesPanel.js b/third_party/WebKit/Source/devtools/front_end/resources/ResourcesPanel.js
index d1f6f83bf94d4caa791e2c716f768cfd9afc31a1..580a5a0bcd27ccac0ec5bf19a81b4011423fb947 100644
--- a/third_party/WebKit/Source/devtools/front_end/resources/ResourcesPanel.js
+++ b/third_party/WebKit/Source/devtools/front_end/resources/ResourcesPanel.js
@@ -128,13 +128,17 @@ WebInspector.ResourcesPanel.prototype = {
         this._databaseModel = WebInspector.DatabaseModel.fromTarget(target);
         this._domStorageModel = WebInspector.DOMStorageModel.fromTarget(target);
 
-        if (target.resourceTreeModel.cachedResourcesLoaded())
-            this._initialize();
-
-        target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, this._initialize, this);
-        target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.WillLoadCachedResources, this._resetWithFrames, this);
         this._databaseModel.addEventListener(WebInspector.DatabaseModel.Events.DatabaseAdded, this._databaseAdded, this);
         this._databaseModel.addEventListener(WebInspector.DatabaseModel.Events.DatabasesRemoved, this._resetWebSQL, this);
+
+        var resourceTreeModel = WebInspector.ResourceTreeModel.fromTarget(target);
+        if (!resourceTreeModel)
+            return;
+        if (resourceTreeModel.cachedResourcesLoaded())
+            this._initialize();
+
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, this._initialize, this);
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.WillLoadCachedResources, this._resetWithFrames, this);
     },
 
     /**
@@ -147,8 +151,11 @@ WebInspector.ResourcesPanel.prototype = {
             return;
         delete this._target;
 
-        target.resourceTreeModel.removeEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, this._initialize, this);
-        target.resourceTreeModel.removeEventListener(WebInspector.ResourceTreeModel.EventTypes.WillLoadCachedResources, this._resetWithFrames, this);
+        var resourceTreeModel = WebInspector.ResourceTreeModel.fromTarget(target);
+        if (resourceTreeModel) {
+            resourceTreeModel.removeEventListener(WebInspector.ResourceTreeModel.EventTypes.CachedResourcesLoaded, this._initialize, this);
+            resourceTreeModel.removeEventListener(WebInspector.ResourceTreeModel.EventTypes.WillLoadCachedResources, this._resetWithFrames, this);
+        }
         this._databaseModel.removeEventListener(WebInspector.DatabaseModel.Events.DatabaseAdded, this._databaseAdded, this);
         this._databaseModel.removeEventListener(WebInspector.DatabaseModel.Events.DatabasesRemoved, this._resetWebSQL, this);
 
@@ -167,8 +174,7 @@ WebInspector.ResourcesPanel.prototype = {
         if (cacheStorageModel)
             cacheStorageModel.enable();
 
-        if (this._target.isPage())
-            this._populateResourceTree();
+        this._populateResourceTree();
         this._populateDOMStorageTree();
         this._populateApplicationCacheTree();
         this.indexedDBListTreeElement._initialize();
@@ -280,10 +286,16 @@ WebInspector.ResourcesPanel.prototype = {
     _populateResourceTree: function()
     {
         this._treeElementForFrameId = {};
-        this._target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameAdded, this._frameAdded, this);
-        this._target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameNavigated, this._frameNavigated, this);
-        this._target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameDetached, this._frameDetached, this);
-        this._target.resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.ResourceAdded, this._resourceAdded, this);
+
+        var resourceTreeModel = WebInspector.ResourceTreeModel.fromTarget(this._target);
+
+        if (!resourceTreeModel)
+            return;
+
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameAdded, this._frameAdded, this);
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameNavigated, this._frameNavigated, this);
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.FrameDetached, this._frameDetached, this);
+        resourceTreeModel.addEventListener(WebInspector.ResourceTreeModel.EventTypes.ResourceAdded, this._resourceAdded, this);
 
         /**
          * @param {!WebInspector.ResourceTreeFrame} frame
@@ -299,7 +311,7 @@ WebInspector.ResourcesPanel.prototype = {
             for (var i = 0; i < resources.length; ++i)
                 this._resourceAdded({data:resources[i]});
         }
-        populateFrame.call(this, this._target.resourceTreeModel.mainFrame);
+        populateFrame.call(this, resourceTreeModel.mainFrame);
     },
 
     _frameAdded: function(event)
@@ -2135,7 +2147,10 @@ WebInspector.ApplicationCacheFrameTreeElement.prototype = {
 
     _refreshTitles: function()
     {
-        var frame = this._storagePanel._target.resourceTreeModel.frameForId(this._frameId);
+        var resourceTreeModel = WebInspector.ResourceTreeModel.fromTarget(this._storagePanel._target);
+        if (!resourceTreeModel)
+            return;
+        var frame = resourceTreeModel.frameForId(this._frameId);
         this.title = frame.displayName();
     },