Bump to v4.12.0.

_mapCacheGet.js

@@ -0,0 +1,17 @@
+define(['./_getMapData'], function(getMapData) {
+
+  /**
+   * Gets the map value for `key`.
+   *
+   * @private
+   * @name get
+   * @memberOf MapCache
+   * @param {string} key The key of the value to get.
+   * @returns {*} Returns the entry value.
+   */
+  function mapCacheGet(key) {
+    return getMapData(this, key).get(key);
+  }
+
+  return mapCacheGet;
+});