bitbake: bitbake: bitbake-worker: Preserve network non-local uid

The NIS can't work when network is dissable, so preserve network for it, the
error is like:

do_ypcall: clnt_call: RPC: Unable to send; errno = Network is unreachable

Note, enable nscd on the build machine might be a solution, but that isn't
reliable since it depends on whether the network function has been cached or
not.

(Bitbake rev: 4eafae7904bae6e5c6bc50356e8a9077f2e207fa)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/utils.py

@@ -1735,3 +1735,19 @@ def environment(**envvars):
                 os.environ[var] = backup[var]
             else:
                 del os.environ[var]
+
+def is_local_uid(uid=''):
+    """
+    Check whether uid is a local one or not.
+    Can't use pwd module since it gets all UIDs, not local ones only.
+    """
+    if not uid:
+        uid = os.getuid()
+    with open('/etc/passwd', 'r') as f:
+        for line in f:
+            line_split = line.split(':')
+            if len(line_split) < 3:
+                continue
+            if str(uid) == line_split[2]:
+                return True
+    return False