Prevent renaming of properties added to Window and Node so that other…

… closure-compiler compiled code doesn't conflict.

externs/shadydom.js

@@ -1,14 +1,30 @@
 /**
- * @fileoverview Externs to upstream to closure compiler
+ * @fileoverview Externs for closure compiler
  * @externs
  */
 
 /**
+ * Upstream to closure-compiler
  * @type {string}
  */
 Element.prototype.slot;
 
 /**
+ * Upstream to closure-compiler
  * @type {Object}
  */
-Node.prototype.__shady;
+Node.prototype.__shady;
+
+/**
+ * Block renaming of properties added to Window to
+ * prevent conflicts with other closure-compiler code.
+ * @type {Object}
+ */
+Window.prototype.__handlers;
+
+/**
+ * Block renaming of properties added to Node to
+ * prevent conflicts with other closure-compiler code.
+ * @type {Object}
+ */
+Node.prototype.__handlers;