camel_stream_printf() is next on the chopping block.
Use g_strdup_printf() or a GString to construct a formatted string in
memory, pass it to camel_stream_write() in one go, and then check for
errors (unless it's a memory stream).
EMFormatHTML now holds a sealed EWebView instead of a public GtkHTML,
accessible through em_format_html_get_web_view().
Rename e_mail_reader_get_html_display() to e_mail_reader_get_formatter()
and have it return an EMFormatHTML instead of an EMFormatHTMLDisplay,
since that's usually the type you want (or else an EMFormat, but never
an EMFormatHTMLDisplay).
