Move internal modules to “internal” folder.

.internal/getSymbols.js

@@ -0,0 +1,25 @@
+import arrayFilter from './.internal/arrayFilter.js';
+import stubArray from './stubArray.js';
+
+/** Built-in value references. */
+const propertyIsEnumerable = Object.prototype.propertyIsEnumerable;
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+const nativeGetSymbols = Object.getOwnPropertySymbols;
+
+/**
+ * Creates an array of the own enumerable symbols of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the array of symbols.
+ */
+const getSymbols = !nativeGetSymbols ? stubArray : object => {
+  if (object == null) {
+    return [];
+  }
+  object = Object(object);
+  return arrayFilter(nativeGetSymbols(object), symbol => propertyIsEnumerable.call(object, symbol));
+};
+
+export default getSymbols;