Fix current animation to fallback to idle on top-down mode

If the entity is eg. a player, performace is dynamic, so the first
```javascript
if (this.performance === _c.DYNAMIC) {
```
always applies. If on top-down mode, we'll also always go to
```javascript
else if (_c.TOP_DOWN) {
```
and this used to always set the animation to "move" and return true (= using non-idle animation).

So it never felt back to idle.

I think this committed code is the intended behavior and my quick test seems to indicate so.