Add ARIA panel to accessibility sidebar pane

third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js

Index: third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js b/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
index ed0d4be3ccadb24ccadcc97d125d56624a9da96c..e617227c9a5a95280762c669639fd799b265a90c 100644
--- a/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
+++ b/third_party/WebKit/Source/devtools/front_end/elements/ElementsPanel.js
@@ -201,15 +201,18 @@ WebInspector.ElementsPanel.prototype = {
     {
         var extensions = self.runtime.extensions("@WebInspector.View");
 
+        var promises = [];
         for (var i = 0; i < extensions.length; ++i) {
             var descriptor = extensions[i].descriptor();
             if (descriptor["location"] !== "elements-panel")
                 continue;
 
             var title = WebInspector.UIString(descriptor["title"]);
-            extensions[i].instancePromise().then(addSidebarView.bind(this, title));
+            promises.push(extensions[i].instancePromise().then(addSidebarView.bind(this, title)));
         }
 
+        Promise.all(promises).then(this._sidebarViewsLoadedForTest.bind(this));
+
         /**
          * @param {string} title
          * @param {!Object} object
@@ -225,6 +228,11 @@ WebInspector.ElementsPanel.prototype = {
         }
     },
 
+    _sidebarViewsLoadedForTest: function()
+    {
+        // For sniffing in tests.
+    },
+
     /**
      * @override
      * @param {!WebInspector.Target} target