ChangeReviewersByEmailIT: Use enableDb/disableDb helper methods

Callers shouldn't depend on the implementation detail of the
NotesMigration, and the implementation will change soon.

Change-Id: I3286ca32efa185cac5066a0c49d758fcae0949b9
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/ChangeReviewersByEmailIT.java b/javatests/com/google/gerrit/acceptance/rest/change/ChangeReviewersByEmailIT.java
index 2a397e4..7b302c4 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/ChangeReviewersByEmailIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/ChangeReviewersByEmailIT.java
@@ -21,6 +21,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.AcceptanceTestRequestScope.Context;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.extensions.api.changes.AddReviewerInput;
@@ -319,14 +320,14 @@
       input.state = state;
       gApi.changes().id(r.getChangeId()).addReviewer(input);
 
-      notesMigration.setFailOnLoadForTest(true);
+      Context oldCtx = disableDb();
       try {
         ChangeInfo info =
             Iterables.getOnlyElement(
                 gApi.changes().query(r.getChangeId()).withOption(DETAILED_LABELS).get());
         assertThat(info.reviewers).isEqualTo(ImmutableMap.of(state, ImmutableList.of(acc)));
       } finally {
-        notesMigration.setFailOnLoadForTest(false);
+        enableDb(oldCtx);
       }
     }
   }