Fix for bug http://www.abisource.com/bugzilla/show_bug.cgi?id=734 .
Modified lines are now redrawn periodically as required.
CVS: ----------------------------------------------------------------------
CVS: Enter Log. Lines beginning with `CVS:' are removed automatically
CVS:
CVS: Committing in .
CVS:
CVS: Modified Files:
CVS: fmt/xp/fl_BlockLayout.cpp fmt/xp/fl_BlockLayout.h
CVS: fmt/xp/fl_DocLayout.cpp fmt/xp/fl_DocLayout.h
CVS: fmt/xp/fl_SectionLayout.cpp fmt/xp/fl_SectionLayout.h
CVS: fmt/xp/fp_Line.cpp fmt/xp/fp_Line.h
CVS: ----------------------------------------------------------------------
