autotest: Extract is_in_{moblab,ssp_moblab,lab} functions

BUG=chromium:878497
TEST=manual

Change-Id: I85a9fb2d664dfaf86168139a4e0b6e077f608ae2
Reviewed-on: https://chromium-review.googlesource.com/1195067
Commit-Ready: Prathmesh Prabhu <pprabhu@chromium.org>
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>
Reviewed-by: Prathmesh Prabhu <pprabhu@chromium.org>
Reviewed-by: Allen Li <ayatane@chromium.org>
diff --git a/server/site_utils.py b/server/site_utils.py
index 71e3150..bc0c22a 100644
--- a/server/site_utils.py
+++ b/server/site_utils.py
@@ -19,6 +19,7 @@
 from autotest_lib.client.bin.result_tools import utils as result_utils
 from autotest_lib.client.bin.result_tools import utils_lib as result_utils_lib
 from autotest_lib.client.bin.result_tools import view as result_view
+from autotest_lib.client.common_lib import lsbrelease_utils
 from autotest_lib.client.common_lib import utils
 from autotest_lib.client.common_lib import error
 from autotest_lib.client.common_lib import file_utils
@@ -339,6 +340,12 @@
     _decode_lab_status(json_status, build)
 
 
+def host_in_lab(hostname):
+    return (not utils.in_moblab_ssp()
+            and not lsbrelease_utils.is_moblab()
+            and utils.host_is_in_lab_zone(hostname))
+
+
 def lock_host_with_labels(afe, lock_manager, labels):
     """Lookup and lock one host that matches the list of input labels.