Thanks for doing all that. I installed your patches into the Emacs 
master, along with the attached further patch which omits the 
undocumented support for escapes like "\N{CJK IDEOGRAPH-3400}" as I 
couldn't see the utility of these over and above plain "\N{U+3400}", 
plus it wasn't clear why CJK ideographs needed special-case names 
whereas other ideographs did not.