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

HTML5 "in row" insertion mode.

This mode handles content inside a <tr> element.

Per HTML5 spec:

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