This copy constructor does what a default copy constructor would do, so it's not necessary. Furthermore, this copy constructor is the only reason why LayoutUnit becomes non-POD, and that triggers a gdb bug, making it impossible to do things like "print location()" when inside some RenderBlock, for instance. Gdb bug http://sourceware.org/bugzilla/show_bug.cgi?id=15154 reported on that.
Created attachment 188890 [details] Patch
Comment on attachment 188890 [details] Patch Clearing flags on attachment: 188890 Committed r143361: <http://trac.webkit.org/changeset/143361>
All reviewed patches have been landed. Closing bug.