DevTools: make extension server a part of core, panels' code should depend on it.

Source/devtools/front_end/extensions/ExtensionPanel.js

Index: Source/devtools/front_end/extensions/ExtensionPanel.js
diff --git a/Source/devtools/front_end/extensions/ExtensionPanel.js b/Source/devtools/front_end/extensions/ExtensionPanel.js
index dd418f26b4707d87b50b25afa784909d97132364..c56375683514e15fea4d87b02ca87246df236ffe 100644
--- a/Source/devtools/front_end/extensions/ExtensionPanel.js
+++ b/Source/devtools/front_end/extensions/ExtensionPanel.js
@@ -145,19 +145,37 @@ WebInspector.ExtensionButton.prototype = {
  * @constructor
  * @extends {WebInspector.SidebarPane}
  * @param {!WebInspector.ExtensionServer} server
+ * @param {string} panelName
  * @param {string} title
  * @param {string} id
  */
-WebInspector.ExtensionSidebarPane = function(server, title, id)
+WebInspector.ExtensionSidebarPane = function(server, panelName, title, id)
 {
     WebInspector.SidebarPane.call(this, title);
     this.setHideOnDetach();
+    this._panelName = panelName;
     this._server = server;
     this._id = id;
 }
 
 WebInspector.ExtensionSidebarPane.prototype = {
     /**
+     * @return {string}
+     */
+    id: function()
+    {
+        return this._id;
+    },
+
+    /**
+     * @return {string}
+     */
+    panelName: function()
+    {
+        return this._panelName;
+    },
+
+    /**
      * @param {!Object} object
      * @param {string} title
      * @param {function(?string=)} callback