* Surface Flinger: Fix an oversight when closing a layer
As the title say.
I also took the liberty of changing the logic on how we select the
current layer being rendered to make it more explicit when opening and
creating layers.
NOTE: Found by Ac_k.
* check for RenderLayerId and not the dictionary size
This fix a possible race condition between the time you create a layer and set the one currently used for rendering
73881fad19