Comment 28 for bug 1269206

for r13135. Some pieces moved from style.h to style-internal.h so the preceding patch broke.

Also includes the patch from bug #1291093, because if that bug remains multiple text decoration changes on multiline text result in the "apply" button on the "text decoration" tab migrating further and further down the screen.

Also includes a fix to preceding versions of this modification that were causing the Text and Font dialog to not pick up font line spacing and size properly on selected text when text decorations were absent.