DEBUG_WRAP_POLYGON_HANDLER would be never defined

Change-Id: I24e1379d136122906deddd298e456728b3be0956
writerfilter: fix include guard

Change-Id: I8c5c8a4e8fbb6e6a2e955c4f544786a2256e6342
writerfilter: check for DEBUG_DOMAINMAPPER, not OSL_DEBUG_LEVEL explicitly

Previously code only built if DEBUG_DOMAINMAPPER was exactly defined
with OSL_DEBUG_LEVEL was > 1, as they these conditions were used for the
same purpose. Change all this dmapper XML dumping code to consistently
use DEBUG_DOMAINMAPPER, so later it'll be possible to change when it's
defined without breaking the build.

Change-Id: I32442cf098162c7d7c9eb7c454094685ab654b74