### 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 (co && co->is_inside_tree()) {
				if (p_clean_all_frames && p_paused_only && co->can_process()) {
					continue;
				}
				co->_mouse_shape_exit(E.key.second);
			}
		}
		shapes_to_erase.push_back(E.key);
	}
	while (shapes_to_erase.size()) {
		physics_2d_shape_mouseover.erase(shapes_to_erase.front()->get());
		shapes_to_erase.pop_front();
	}
}
void Viewport::_gui_grab_click_focus(Control *p_control) {
	gui.mouse_click_grabber = p_control;
	call_deferred(SNAME("_post_gui_grab_click_focus"));
}
void Viewport::_post_gui_grab_click_focus() {
	Control *focus_grabber = gui.mouse_click_grabber;
	if (!focus_grabber) {
		
		return;
	}
	gui.mouse_click_grabber = nullptr;
	if (gui.mouse_focus) {
		if (gui.mouse_focus == focus_grabber) {
			return;
		}
		BitField<MouseButtonMask> mask = gui.mouse_focus_mask;