### 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)

ClassDB::bind_method(D_METHOD("set_size", "size"), &SubViewport::set_size);
	ClassDB::bind_method(D_METHOD("get_size"), &SubViewport::get_size);
	ClassDB::bind_method(D_METHOD("set_size_2d_override", "size"), &SubViewport::set_size_2d_override);
	ClassDB::bind_method(D_METHOD("get_size_2d_override"), &SubViewport::get_size_2d_override);
	ClassDB::bind_method(D_METHOD("set_size_2d_override_stretch", "enable"), &SubViewport::set_size_2d_override_stretch);
	ClassDB::bind_method(D_METHOD("is_size_2d_override_stretch_enabled"), &SubViewport::is_size_2d_override_stretch_enabled);
	ClassDB::bind_method(D_METHOD("set_update_mode", "mode"), &SubViewport::set_update_mode);
	ClassDB::bind_method(D_METHOD("get_update_mode"), &SubViewport::get_update_mode);
	ClassDB::bind_method(D_METHOD("set_clear_mode", "mode"), &SubViewport::set_clear_mode);
	ClassDB::bind_method(D_METHOD("get_clear_mode"), &SubViewport::get_clear_mode);
	ADD_PROPERTY(PropertyInfo(Variant::VECTOR2I, "size", PROPERTY_HINT_NONE, "suffix:px"), "set_size", "get_size");
	ADD_PROPERTY(PropertyInfo(Variant::VECTOR2I, "size_2d_override", PROPERTY_HINT_NONE, "suffix:px"), "set_size_2d_override", "get_size_2d_override");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "size_2d_override_stretch"), "set_size_2d_override_stretch", "is_size_2d_override_stretch_enabled");
	ADD_GROUP("Render Target", "render_target_");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "render_target_clear_mode", PROPERTY_HINT_ENUM, "Always,Never,Next Frame"), "set_clear_mode", "get_clear_mode");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "render_target_update_mode", PROPERTY_HINT_ENUM, "Disabled,Once,When Visible,When Parent Visible,Always"), "set_update_mode", "get_update_mode");
	BIND_ENUM_CONSTANT(CLEAR_MODE_ALWAYS);
	BIND_ENUM_CONSTANT(CLEAR_MODE_NEVER);
	BIND_ENUM_CONSTANT(CLEAR_MODE_ONCE);
	BIND_ENUM_CONSTANT(UPDATE_DISABLED);
	BIND_ENUM_CONSTANT(UPDATE_ONCE);
	BIND_ENUM_CONSTANT(UPDATE_WHEN_VISIBLE);
	BIND_ENUM_CONSTANT(UPDATE_WHEN_PARENT_VISIBLE);
	BIND_ENUM_CONSTANT(UPDATE_ALWAYS);
}
void SubViewport::_validate_property(PropertyInfo &p_property) const {