At the moment TextEditorHighlighter's properties are stored as a sparse array. Having them in a dense array seems to be both more convenient and faster for later processing.
Created attachment 180499 [details] Patch
Comment on attachment 180499 [details] Patch Clearing flags on attachment: 180499 Committed r138438: <http://trac.webkit.org/changeset/138438>
All reviewed patches have been landed. Closing bug.