Web: Skip useless empty elements when seeking first context in document
Web: Skip useless empty elements when seeking first context in document

There shouldn't be useless empty elements at the top of a document. But
authors, along with Thunderbird.... Therefore when seeking the first
context in the document (e.g. when pressing Ctrl+Home), start with the
first child that isn't a useless empty element.

GNOME/orca,GNOME/orca,GNOME/orca,GNOME/orca