templatekw: apply manifest template only if ctx.manifestnode() exists...
templatekw: apply manifest template only if ctx.manifestnode() exists
This will prevent crash by "hg log -r 'wdir()' -Tdefault". We could use the
pseudo ff... hash introduced by 183965a00c76, but it isn't proven idea yet.
For now, I want to make "hg log" just works in order to test 'wdir()' revset.
Note that unlike its name, "{manifest}" is not a list of files in that
revision, but a pair of (manifestrev, manifestnode).