SurfaceTexture: Reset buffer values on disconnect.

When the surface texture client disconnects, reset the values set
for buffer width, height, transform and format. This is to ensure
that the same surface texture can be used by another client with
different parameters without any corruptions.

Change-Id: I1e158f4641d7b06cea9976ad2827c7b12c95f538
CRs-Fixed: 347382