PureHTML.TreeBuilder.Modes.InCell (PureHTML v0.4.0)

HTML5 "in cell" insertion mode.

This mode handles content inside a <td> or <th> element.

Per HTML5 spec:

Character tokens: process using "in body" rules
Comments: process using "in body" rules
DOCTYPE: parse error, ignore
Start tags:
- caption, col, colgroup, tbody, td, tfoot, th, thead, tr: close cell, reprocess
- Anything else: process using "in body" rules
End tags:
- td, th: close cell, switch to "in row"
- body, caption, col, colgroup, html: parse error, ignore
- table, tbody, tfoot, thead, tr: close cell if in scope, reprocess
- Anything else: process using "in body" rules