When a layer sets a cached image's className to something else than .olTileImage (e.g. by setting .olTileReplacing), we should not keep the image in the cache any more, because it may no longer be valid.
When a layer sets a cached image's className to something else than .olTileImage (e.g. by setting .olTileReplacing), we should not keep the image in the cache any more, because it may no longer be valid.