### Godot version

v4.1.stable.official [970459615]

### System information

Godot v4.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1660 Ti (NVIDIA; 31.0.15.3598) - AMD Ryzen 7 3700X 8-Core Processor (16 Threads)

### Issue description

is_input_handled() is returning True, even though set_input_as_handled() has not been called.

Example:
`func _input_event(viewport, event, shape_idx):
	print(viewport.is_input_handled())`

Returns 'True', should return 'False'

### Steps to reproduce

1. Create a new project and add a Node2D as the root
2. Add a child Area2D node containing a CollisionShape2D and a Sprite2D
3. Either create the _input_event(viewport, event, shape_idx) or connect _on_input_event(viewport, event, shape_idx)
4. Print viewport.is_input_handled()
5. True is printed.

### Minimal reproduction project

[input_test.zip](https://github.com/godotengine/godot/files/12063748/input_test.zip)

if (get_base_window() == p_window) {
		gui_release_focus();
	}
}
bool Viewport::_gui_control_has_focus(const Control *p_control) {
	return gui.key_focus == p_control;
}
void Viewport::_gui_control_grab_focus(Control *p_control) {
	if (gui.key_focus && gui.key_focus == p_control) {
		
		return;
	}
	get_tree()->call_group("_viewports", "_gui_remove_focus_for_window", (Node *)get_base_window());
	if (p_control->is_inside_tree() && p_control->get_viewport() == this) {
		gui.key_focus = p_control;
		emit_signal(SNAME("gui_focus_changed"), p_control);
		p_control->notification(Control::NOTIFICATION_FOCUS_ENTER);
		p_control->queue_redraw();
	}
}
void Viewport::_gui_accept_event() {
	gui.key_event_accepted = true;
	if (is_inside_tree()) {
		set_input_as_handled();
	}
}
void Viewport::_drop_mouse_over() {