Sets the buffer contained by the snip, relasing the old buffer in the snip (if any). If the new buffer already has an administrator, then the new buffer is not installed into the snip.
When a wx:media-snip% object is not inserted in a buffer, it does not have an administrator. During this time, it does not give its contained buffer an administrator, either. The administratorless contained buffer can therefore "defect" to some other display with an administrator. When a contained buffer defects and the snip is eventually inserted into a different buffer, the snip drops the traitor contained buffer, setting its contained buffer to null.