TiledDrawingArea: Fix issues where the tiles of the previous scale would be removed too early.
Created attachment 105945 [details]
Comment on attachment 105945 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=105945&action=review
> + be replaced by the current incomplete tile set which may contain no tile at all.
Committed r94678: <http://trac.webkit.org/changeset/94678>