Add a minimal Security panel to DevTools (behind a hidden experiment).

Source/devtools/front_end/security/SecurityPanel.js

+// Copyright 2015 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.Panel}
+ * @implements {WebInspector.TargetManager.Observer}
+ */
+WebInspector.SecurityPanel = function() {
+    WebInspector.Panel.call(this, "security");
+    this.registerRequiredCSS("security/securityPanel.css");
+
+    WebInspector.targetManager.addModelListener(WebInspector.SecurityManager, WebInspector.SecurityManager.EventTypes.SecurityStateChanged, this._onSecurityStateChanged, this);
+
+    this.element.appendChild(this._createSecurityStateSection());
+}
+
+WebInspector.SecurityPanel.prototype = {
+    _updateSecurityState: function (newSecurityState)
+    {
+        // Remove old state.
+        // It's safe to call this even when this.securityState is undefined.
+        this.lockIcon.classList.remove(this.securityState);
+
+        // Add new state.
+        this.securityState = newSecurityState;
+        this.lockIcon.classList.add(this.securityState);
+        this.securityStateText.textContent = this.securityState;
+    },
+
+    _onSecurityStateChanged: function (event)
+    {
+        this._updateSecurityState(event.data);
+    },
+
+    _createSecurityStateSection: function()
+    {
+        var securityStateSection = createElement("div");
+
+        this.lockIcon = createElementWithClass("div", "lock-icon");
+        securityStateSection.appendChild(this.lockIcon);
+
+        this.securityStateText = createElementWithClass("div", "security-state");
+        securityStateSection.appendChild(this.securityStateText);
+
+        this._updateSecurityState("unknown");
+
+        return securityStateSection;
+    },
+
+    /**
+      * @override
+      * @param {!WebInspector.Target} target
+      */
+    targetAdded: function(target)
+    {
+    },
+
+    __proto__: WebInspector.Panel.prototype
+}
+
+/**
+ * @return {!WebInspector.SecurityPanel}
+ */
+WebInspector.SecurityPanel._instance = function()
+{
+    if (!WebInspector.SecurityPanel._instanceObject)
+        WebInspector.SecurityPanel._instanceObject = new WebInspector.SecurityPanel();
+    return WebInspector.SecurityPanel._instanceObject;
+}
+
+/**
+ * @constructor
+ * @implements {WebInspector.PanelFactory}
+ */
+WebInspector.SecurityPanelFactory = function()
+{
+}
+
+WebInspector.SecurityPanelFactory.prototype = {
+    /**
+     * @override
+     * @return {!WebInspector.Panel}
+     */
+    createPanel: function()
+    {
+        return WebInspector.SecurityPanel._instance();
+    }
+}