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

Source/devtools/front_end/common/DOMExtension.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 279 matching lines @@
  * @param {!Event} event
  * @return {boolean}
  */
 Element.prototype.containsEventPoint = function(event)
 {
     var box = this.getBoundingClientRect();
     return box.left < event.x  && event.x < box.right &&
            box.top < event.y && event.y < box.bottom;
 }
 
+/**
+ * @param {!Array.<string>} nameArray
+ * @return {?Node}
+ */
 Node.prototype.enclosingNodeOrSelfWithNodeNameInArray = function(nameArray)
 {
-    for (var node = this; node && node !== this.ownerDocument; node = node.parentNode)
-        for (var i = 0; i < nameArray.length; ++i)
+    for (var node = this; node && node !== this.ownerDocument; node = node.parentNode) {
+        for (var i = 0; i < nameArray.length; ++i) {
             if (node.nodeName.toLowerCase() === nameArray[i].toLowerCase())
                 return node;
+        }
+    }
     return null;
 }
 
+/**
+ * @param {string} nodeName
+ * @return {?Node}
+ */
 Node.prototype.enclosingNodeOrSelfWithNodeName = function(nodeName)
 {
     return this.enclosingNodeOrSelfWithNodeNameInArray([nodeName]);
 }
 
 /**
  * @param {string} className
  * @param {!Element=} stayWithin
+ * @return {?Element}
  */
 Node.prototype.enclosingNodeOrSelfWithClass = function(className, stayWithin)
 {
-    for (var node = this; node && node !== stayWithin && node !== this.ownerDocument; node = node.parentNode)
+    for (var node = this; node && node !== stayWithin && node !== this.ownerDocument; node = node.parentNode) {
         if (node.nodeType === Node.ELEMENT_NODE && node.classList.contains(className))
-            return node;
+            return /** @type {!Element} */ (node);
+    }
     return null;
 }
 
+/**
+ * @param {string} query
+ * @return {?Node}
+ */
 Element.prototype.query = function(query)
 {
     return this.ownerDocument.evaluate(query, this, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
 }
 
 Element.prototype.removeChildren = function()
 {
     if (this.firstChild)
         this.textContent = "";
 }
@@ skipping 149 matching lines @@
             break;
 
         curElement = curWindow.frameElement;
         curWindow = curWindow.parent;
     }
 
     return elementOffset;
 }
 
 /**
- * @param {!Window} targetWindow
+ * @param {!Window=} targetWindow
  * @return {!AnchorBox}
  */
 Element.prototype.boxInWindow = function(targetWindow)
 {
     targetWindow = targetWindow || this.ownerDocument.defaultView;
 
     var anchorBox = this.offsetRelativeToWindow(window);
     anchorBox.width = Math.min(this.offsetWidth, window.innerWidth - anchorBox.x);
     anchorBox.height = Math.min(this.offsetHeight, window.innerHeight - anchorBox.y);
 
@@ skipping 167 matching lines @@
  */
 function isEnterKey(event) {
     // Check if in IME.
     return event.keyCode !== 229 && event.keyIdentifier === "Enter";
 }
 
 function consumeEvent(e)
 {
     e.consume();
 }