* cygheap.h (cygheap_user::winname): New field.

* cygheap.h (cygheap_user::winname): New field.
* cygheap.cc (cygheap_user::set_name): Clear winname when name changes.
* uinfo.cc (cygheap_user::env_logsrv): Avoid calculating server when Windows
user == SYSTEM.
(cygheap_user::env_domain): Set winname here too.
(cygheap_user::env_userprofile): Eliminate superfluous tests.
(cygheap_user::env_name): Seed winname by calling env_domain().