LibJS: Remove gc from the global object

No other engine defines this function, so it is an observable difference
of our engine. This traces back to the earliest days of LibJS.

We now define `gc` in just the test-js and test262 runners.

Libraries/LibJS/Contrib/Test262/262Object.cpp

@@ -40,9 +40,9 @@ void $262Object::initialize(Realm& realm)
     define_native_function(realm, "createRealm"_utf16_fly_string, create_realm, 0, attr);
     define_native_function(realm, "detachArrayBuffer"_utf16_fly_string, detach_array_buffer, 1, attr);
     define_native_function(realm, "evalScript"_utf16_fly_string, eval_script, 1, attr);
+    define_native_function(realm, "gc"_utf16_fly_string, collect_garbage, 1, attr);
 
     define_direct_property("agent"_utf16_fly_string, m_agent, attr);
-    define_direct_property("gc"_utf16_fly_string, realm.global_object().get_without_side_effects("gc"_utf16_fly_string), attr);
     define_direct_property("global"_utf16_fly_string, &realm.global_object(), attr);
     define_direct_property("IsHTMLDDA"_utf16_fly_string, m_is_htmldda, attr);
 }
@@ -60,6 +60,12 @@ JS_DEFINE_NATIVE_FUNCTION($262Object::clear_kept_objects)
     return js_undefined();
 }
 
+JS_DEFINE_NATIVE_FUNCTION($262Object::collect_garbage)
+{
+    vm.heap().collect_garbage();
+    return JS::js_undefined();
+}
+
 JS_DEFINE_NATIVE_FUNCTION($262Object::create_realm)
 {
     GC::Ptr<JS::Test262::GlobalObject> global_object;

Libraries/LibJS/Contrib/Test262/262Object.h

@@ -30,6 +30,7 @@ private:
     GC::Ptr<IsHTMLDDA> m_is_htmldda;
 
     JS_DECLARE_NATIVE_FUNCTION(clear_kept_objects);
+    JS_DECLARE_NATIVE_FUNCTION(collect_garbage);
     JS_DECLARE_NATIVE_FUNCTION(create_realm);
     JS_DECLARE_NATIVE_FUNCTION(detach_array_buffer);
     JS_DECLARE_NATIVE_FUNCTION(eval_script);

Libraries/LibJS/Runtime/CommonPropertyNames.h

@@ -194,7 +194,6 @@ namespace JS {
     P(fromHex)                               \
     P(fround)                                \
     P(Function)                              \
-    P(gc)                                    \
     P(get)                                   \
     P(getBigInt64)                           \
     P(getBigUint64)                          \

Libraries/LibJS/Runtime/GlobalObject.cpp

@@ -185,25 +185,8 @@ void set_default_global_bindings(Realm& realm)
     // 3. Return unused.
 }
 
-void GlobalObject::initialize(Realm& realm)
-{
-    Base::initialize(realm);
-
-    auto& vm = this->vm();
-
-    // Non-standard
-    u8 attr = Attribute::Writable | Attribute::Configurable;
-    define_native_function(realm, vm.names.gc, gc, 0, attr);
-}
-
 GlobalObject::~GlobalObject() = default;
 
-JS_DEFINE_NATIVE_FUNCTION(GlobalObject::gc)
-{
-    vm.heap().collect_garbage();
-    return js_undefined();
-}
-
 // 19.2.1 eval ( x ), https://tc39.es/ecma262/#sec-eval-x
 JS_DEFINE_NATIVE_FUNCTION(GlobalObject::eval)
 {

Libraries/LibJS/Runtime/GlobalObject.h

@@ -21,7 +21,6 @@ class JS_API GlobalObject : public Object {
     friend class Intrinsics;
 
 public:
-    virtual void initialize(Realm&) override;
     virtual ~GlobalObject() override;
 
 protected:
@@ -30,7 +29,6 @@ protected:
 private:
     virtual bool is_global_object() const final { return true; }
 
-    JS_DECLARE_NATIVE_FUNCTION(gc);
     JS_DECLARE_NATIVE_FUNCTION(is_nan);
     JS_DECLARE_NATIVE_FUNCTION(is_finite);
     JS_DECLARE_NATIVE_FUNCTION(parse_float);

Tests/LibJS/test-js.cpp

@@ -26,6 +26,12 @@ TESTJS_GLOBAL_FUNCTION(can_parse_source, canParseSource)
     return JS::Value(!script.is_error());
 }
 
+TESTJS_GLOBAL_FUNCTION(collect_garbage, gc)
+{
+    vm.heap().collect_garbage();
+    return JS::js_undefined();
+}
+
 // Based on $262.evalScript
 TESTJS_GLOBAL_FUNCTION(evaluate_source, evaluateSource)
 {