Bump to v4.1.0.

_hashHas.js

@@ -0,0 +1,25 @@
+define(['./_nativeCreate'], function(nativeCreate) {
+
+  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
+  var undefined;
+
+  /** Used for built-in method references. */
+  var objectProto = Object.prototype;
+
+  /** Used to check objects for own properties. */
+  var hasOwnProperty = objectProto.hasOwnProperty;
+
+  /**
+   * Checks if a hash value for `key` exists.
+   *
+   * @private
+   * @param {Object} hash The hash to query.
+   * @param {string} key The key of the entry to check.
+   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
+   */
+  function hashHas(hash, key) {
+    return nativeCreate ? hash[key] !== undefined : hasOwnProperty.call(hash, key);
+  }
+
+  return hashHas;
+});