DevTools: Add JSDoc for static methods, fix JSDoc types and induced errors

Source/devtools/front_end/ui/SidebarPane.js

Index: Source/devtools/front_end/ui/SidebarPane.js
diff --git a/Source/devtools/front_end/ui/SidebarPane.js b/Source/devtools/front_end/ui/SidebarPane.js
index 5064d6698a993ba5d58bec375857e118c4dbf670..85ac23037ad080e6660021eaebaab2a37c50cc14 100644
--- a/Source/devtools/front_end/ui/SidebarPane.js
+++ b/Source/devtools/front_end/ui/SidebarPane.js
@@ -126,7 +126,7 @@ WebInspector.SidebarPaneTitle.prototype = {
     _expand: function()
     {
         this.element.classList.add("expanded");
-        this._pane.show(this.element.parentNode, this.element.nextSibling);
+        this._pane.show(this.element.parentElement, /** @type {?Element} */ (this.element.nextSibling));

[aandrey, 2014/06/17 11:33:54]

should be no cast (e.g. let pane.show() accept undefined)

[apavlov, 2014/06/17 12:46:04]

This cast is about Node->Element, not about undefined->null

     },
 
     _collapse: function()
@@ -145,7 +145,7 @@ WebInspector.SidebarPaneTitle.prototype = {
     },
 
     /**
-     * @param {!Event} event
+     * @param {?Event} event
      */
     _onTitleKeyDown: function(event)
     {