Also add missing DeleteCriticalSection.

quartz: Stop DSound buffer playback when the filter is paused or stopped, not the next time it's processed.

My last patch was wrong and caused some nasty regressions. Mapping 
CLR_DEFAULT to the global defaults seem to be what native does.

When using pbuffer or back buffer offscreen rendering the content of
the drawable will have been overwritten. Thus the texture has to be
written into the drawable. An exception is the (pretty common) case
that the whole render target is cleared before rendering to it.

The state handler binds index buffer 0 when a user pointer is used. Likewise the real index
buffer has to be restored when switching back to drawing from index buffers.