fdo#87110: xmloff: don't catch IllegalArgumentException here

There are at least 2 callers of InsertTextContent() that have
non-trivial catch handlers for this exception, which aren't called now.

(regression from bebf8ccfba37f77d6a43c7874249b31736467b17)

Change-Id: I085b710dfd5877e9b7e71610951543eddf6a6e46
sw: don't assert when SwXBookmark creates duplicate CrossRef*Bookmark

The bugdoc of fdo#87110 has a couple such duplicates.  Check for it and
let SwXBookmark throw an IllegalArgumentException.

Change-Id: I460dc3a8d9c554c194a32a73526e13422ddd1c52
xmloff: make the export of the horrible field marks aware of auto-styles

When exporting the .DOC bugdoc of fdo#87110 to ODF, the auto-styles
export will iterate over the fieldmarks in the page header and add the
attributes for them but not export the elements, so the first auto-style
gets a bunch of duplicate attributes.

Change-Id: I3fcf39f03e3d9ae5fca661efa7eb4bbb3eab9f5c