LibJS: Add the Intl namespace object :^)

This is the start of implementing ECMA-402 in LibJS, better known as the
ECMAScript Internationalization API.

Much like Temporal this gets its own subdirectory (Runtime/Intl/) as
well as a new C++ namespace (JS::Intl) so we don't have to prefix all
the files and classes with "Intl".

https://tc39.es/ecma402/

Userland/Libraries/LibJS/CMakeLists.txt

@@ -72,6 +72,7 @@ set(SOURCES
     Runtime/GlobalEnvironment.cpp
     Runtime/GlobalObject.cpp
     Runtime/IndexedProperties.cpp
+    Runtime/Intl/Intl.cpp
     Runtime/IteratorOperations.cpp
     Runtime/IteratorPrototype.cpp
     Runtime/JSONObject.cpp

Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h

@@ -25,6 +25,7 @@ namespace JS {
     P(EPSILON)                               \
     P(Function)                              \
     P(Infinity)                              \
+    P(Intl)                                  \
     P(JSON)                                  \
     P(LN10)                                  \
     P(LN2)                                   \

Userland/Libraries/LibJS/Runtime/GlobalObject.cpp

@@ -41,6 +41,7 @@
 #include <LibJS/Runtime/GeneratorObjectPrototype.h>
 #include <LibJS/Runtime/GlobalEnvironment.h>
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Intl/Intl.h>
 #include <LibJS/Runtime/IteratorPrototype.h>
 #include <LibJS/Runtime/JSONObject.h>
 #include <LibJS/Runtime/MapConstructor.h>
@@ -203,6 +204,7 @@ void GlobalObject::initialize_global_object()
     define_direct_property(vm.names.Math, heap().allocate<MathObject>(*this, *this), attr);
     define_direct_property(vm.names.JSON, heap().allocate<JSONObject>(*this, *this), attr);
     define_direct_property(vm.names.Reflect, heap().allocate<ReflectObject>(*this, *this), attr);
+    define_direct_property(vm.names.Intl, heap().allocate<Intl::Intl>(*this, *this), attr);
     define_direct_property(vm.names.Temporal, heap().allocate<Temporal::Temporal>(*this, *this), attr);
 
     // This must be initialized before allocating AggregateErrorConstructor, which uses ErrorConstructor as its prototype.

Userland/Libraries/LibJS/Runtime/Intl/Intl.cpp

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Intl/Intl.h>
+
+namespace JS::Intl {
+
+// 8 The Intl Object, https://tc39.es/ecma402/#intl-object
+Intl::Intl(GlobalObject& global_object)
+    : Object(*global_object.object_prototype())
+{
+}
+
+void Intl::initialize(GlobalObject& global_object)
+{
+    Object::initialize(global_object);
+}
+
+}

Userland/Libraries/LibJS/Runtime/Intl/Intl.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibJS/Runtime/Object.h>
+
+namespace JS::Intl {
+
+class Intl final : public Object {
+    JS_OBJECT(Intl, Object);
+
+public:
+    explicit Intl(GlobalObject&);
+    virtual void initialize(GlobalObject&) override;
+    virtual ~Intl() override = default;
+};
+
+}