Add request-level caching for privileged queries.

dashboard/dashboard/datastore_hooks_test.py

Index: dashboard/dashboard/datastore_hooks_test.py
diff --git a/dashboard/dashboard/datastore_hooks_test.py b/dashboard/dashboard/datastore_hooks_test.py
index 05cd228aca50ecb32e0c9d0655d14190a4ed956a..d117bd2edc9519a60e7ed2ad703cb0787844c00f 100644
--- a/dashboard/dashboard/datastore_hooks_test.py
+++ b/dashboard/dashboard/datastore_hooks_test.py
@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import unittest
+import webapp2
 
 from google.appengine.ext import ndb
 
@@ -175,6 +176,13 @@ class DatastoreHooksTest(testing_common.TestCase):
       self.assertEqual(1, len(sheriffs))
       self.assertEqual('external', sheriffs[0].key.string_id())
       self.assertEqual('foo@chromium.org', sheriffs[0].email)
+    request = webapp2.get_request()
+    if request.registry.get('single_privileged') is not None:
+      self.assertIsNone(request.registry.get('privileged_cached'))
+    elif include_internal:
+      self.assertTrue(request.registry.get('privileged_cached'))
+    else:
+      self.assertFalse(request.registry.get('privileged_cached'))
 
   def testQuery_NoUser_InternalOnlyNotFetched(self):
     self.UnsetCurrentUser()
@@ -261,6 +269,13 @@ class DatastoreHooksTest(testing_common.TestCase):
     datastore_hooks.SetPrivilegedRequest()
     self._CheckGet(include_internal=True)
 
+  def testGet_CachedPrivilege(self):
+    request = webapp2.get_request()
+    request.registry['privileged_cached'] = True
+    self._CheckGet(include_internal=True)
+    request.registry['privileged_cached'] = False
+    self._CheckGet(include_internal=False)
+
 
 if __name__ == '__main__':
   unittest.main()