Don't try to make React elements immutable

package.json

@@ -16,6 +16,7 @@
     "mocha": "2.4.5",
     "mocha-istanbul": "0.2.0",
     "mocha-lcov-reporter": "1.2.0",
+    "react": "^15.0.1",
     "zuul": "3.9.0"
   },
   "scripts": {

seamless-immutable.development.js

@@ -1,6 +1,10 @@
 (function() {
   "use strict";
 
+  // https://github.com/facebook/react/blob/v15.0.1/src/isomorphic/classic/element/ReactElement.js#L21
+  var REACT_ELEMENT_TYPE = typeof Symbol === 'function' && Symbol.for && Symbol.for('react.element');
+  var REACT_ELEMENT_TYPE_FALLBACK = 0xeac7;
+
   function addPropertyTo(target, methodName, value) {
     Object.defineProperty(target, methodName, {
       enumerable: false,
@@ -497,8 +501,16 @@
     return makeImmutable(obj, mutatingObjectMethods);
   }
 
+  // Returns true if object is a valid react element
+  // https://github.com/facebook/react/blob/v15.0.1/src/isomorphic/classic/element/ReactElement.js#L326
+  function isReactElement(obj) {
+    return typeof obj === 'object' &&
+           obj !== null &&
+           (obj.$$typeof === REACT_ELEMENT_TYPE_FALLBACK || obj.$$typeof === REACT_ELEMENT_TYPE);
+  }
+
   function Immutable(obj, options, stackRemaining) {
-    if (isImmutable(obj)) {
+    if (isImmutable(obj) || isReactElement(obj)) {
       return obj;
     } else if (obj instanceof Array) {
       return makeImmutableArray(obj.slice());