Revert "[autotest] Use AfeHostInfoStore to obtain host information ..."

Something in adb_host pulled in a depepdency on PIL library which is
breaking chromeos-admin's test_push task. This CL added an implicit
import to server/hosts/__init__.py which lead to this chain of imports.
Try to remove this to see if the dependency disappears.

Note that the CL itself was not incorrect. We do want to use HostInfo
for test_push. The fact that chromeos-admin's server_management_lib
imports test_push is broken.

BUG=None
TEST=None

This reverts commit c0e976d011d55fa6f00c67fd65d24e6e2646fd6d.

Change-Id: I7fd3cd55e46c41ffdf944907211fe9f0c7d6facb
Reviewed-on: https://chromium-review.googlesource.com/484627
Reviewed-by: Shuqian Zhao <shuqianz@chromium.org>
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>
diff --git a/site_utils/test_push.py b/site_utils/test_push.py
index e7246d1..be437b9 100755
--- a/site_utils/test_push.py
+++ b/site_utils/test_push.py
@@ -46,7 +46,6 @@
 from autotest_lib.server import utils
 from autotest_lib.server.cros import provision
 from autotest_lib.server.cros.dynamic_suite import frontend_wrappers
-from autotest_lib.server.hosts import afe_store
 from autotest_lib.site_utils import gmail_lib
 from autotest_lib.site_utils.suite_scheduler import constants
 
@@ -380,12 +379,11 @@
             for job_id in job_ids]
     hostnames = set([hqe.host.hostname for hqe in hqes])
     for hostname in hostnames:
-        host_info_store = afe_store.AfeStore(hostname, AFE)
-        info = host_info_store.get()
-        if info.build != build:
+        found_build = site_utils.get_build_from_afe(hostname, AFE)
+        if found_build != build:
             raise TestPushException('DUT is not imaged properly. Host %s has '
                                     'build %s, while build %s is expected.' %
-                                    (hostname, info.build, build))
+                                    (hostname, found_build, build))
 
 
 def test_suite(suite_name, expected_results, arguments, use_shard=False,