server: Mark the process as disconnected from desktop/winstation before closing its handles.

dlls/kernel32/tests/process.c

@@ -1957,7 +1957,6 @@ static void test_TerminateProcess(void)
 
     SetLastError(0xdeadbeef);
     ret = TerminateProcess(pi.hProcess, 0);
-todo_wine
     ok(ret, "TerminateProcess error %u\n", GetLastError());
 
     CloseHandle(pi.hProcess);

server/process.c

@@ -628,9 +628,9 @@ static void process_killed( struct process *process )
     assert( list_empty( &process->thread_list ));
     process->end_time = current_time;
     if (!process->is_system) close_process_desktop( process );
-    close_process_handles( process );
     process->winstation = 0;
     process->desktop = 0;
+    close_process_handles( process );
     if (process->idle_event)
     {
         release_object( process->idle_event );