request also a stencil size

Change-Id: Ib3b8b70aa50dd1a42108e3e9091350bf1d315b03
vcl: OpenGL texture creation debug.

Change-Id: I6a21c89329d9e9396ed16ce58b184339719adab7
vcl: use resetToReInitialize to avoid context problems on Windows.

It appears that we have to do this for VirtualDevices, where we have
freed / re-allocated the underlying resource, or we fail to switch the
current context, and render to the wrong place, before blatting a
blank texture over the top of it.

Change-Id: I0253f216ea7dc9786374dc83ca38f4f6295e3035