build(webpack): Fix the request of a dependency is an expression (#337)

* build(webpack): Fix the request of a dependency is an expression

Critical dependency: the request of a dependency is an expression

* style: Fix spaces after object literal braces

scripts/webpack-helper.js

@@ -0,0 +1,5 @@
+const path = require('path');
+
+module.exports.root = function root(dir, __path) {
+    return path.join(dir, __path);
+};