LibJS: Let NewGlobalEnvironment take a plain Object

The object is passed directly to NewObjectEnvironment, which has no
requirement for this being a JS::GlobalObject. This is needed for the
next change, which will make Realm store a plain Object as for the
global object as well.

Userland/Libraries/LibJS/Runtime/GlobalEnvironment.cpp

@@ -15,7 +15,7 @@
 namespace JS {
 
 // 9.1.2.5 NewGlobalEnvironment ( G, thisValue ), https://tc39.es/ecma262/#sec-newglobalenvironment
-GlobalEnvironment::GlobalEnvironment(GlobalObject& global_object, Object& this_value)
+GlobalEnvironment::GlobalEnvironment(Object& global_object, Object& this_value)
     : Environment(nullptr)
     , m_global_this_value(&this_value)
 {

Userland/Libraries/LibJS/Runtime/GlobalEnvironment.h

@@ -14,7 +14,7 @@ class GlobalEnvironment final : public Environment {
     JS_ENVIRONMENT(GlobalEnvironment, Environment);
 
 public:
-    GlobalEnvironment(GlobalObject&, Object& this_value);
+    GlobalEnvironment(Object&, Object& this_value);
 
     virtual bool has_this_binding() const final { return true; }
     virtual ThrowCompletionOr<Value> get_this_binding(VM&) const final;