feat(ContextElementDependency): make serializable

lib/dependencies/ContextElementDependency.js

@@ -5,11 +5,13 @@
 
 "use strict";
 
+const makeSerializable = require("../util/makeSerializable");
 const ModuleDependency = require("./ModuleDependency");
 
 class ContextElementDependency extends ModuleDependency {
 	constructor(request, userRequest) {
 		super(request);
+
 		if (userRequest) {
 			this.userRequest = userRequest;
 		}
@@ -18,6 +20,27 @@ class ContextElementDependency extends ModuleDependency {
 	get type() {
 		return "context element";
 	}
+
+	serialize(context) {
+		const { write } = context;
+
+		write(this.userRequest);
+
+		super.serialize(context);
+	}
+
+	deserialize(context) {
+		const { read } = context;
+
+		this.userRequest = read();
+
+		super.deserialize(context);
+	}
 }
 
+makeSerializable(
+	ContextElementDependency,
+	"webpack/lib/dependencies/ContextElementDependency"
+);
+
 module.exports = ContextElementDependency;