diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/git/MergeOp.java b/gerrit-server/src/main/java/com/google/gerrit/server/git/MergeOp.java
index f9902b223f..785cc88292 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/git/MergeOp.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/git/MergeOp.java
@@ -276,6 +276,7 @@ public class MergeOp implements AutoCloseable {
   }
   private Timestamp ts;
   private String submissionId;
+  private IdentifiedUser caller;
 
   private ReviewDb db;
 
@@ -475,6 +476,7 @@ public class MergeOp implements AutoCloseable {
   public void merge(ReviewDb db, Change change, IdentifiedUser caller,
       boolean checkSubmitRules) throws NoSuchChangeException,
       OrmException, ResourceConflictException {
+    this.caller = caller;
     updateSubmissionId(change);
     this.db = db;
     logDebug("Beginning integration of {}", change);
@@ -488,7 +490,7 @@ public class MergeOp implements AutoCloseable {
         failFast(cs); // Done checks that don't involve opening repo.
       }
       try {
-        integrateIntoHistory(cs, caller);
+        integrateIntoHistory(cs);
       } catch (IntegrationException e) {
         logError("Merge Conflict", e);
         throw new ResourceConflictException("Merge Conflict", e);
@@ -520,7 +522,7 @@ public class MergeOp implements AutoCloseable {
     throw new ResourceConflictException(msg + Joiner.on('\n').join(ps));
   }
 
-  private void integrateIntoHistory(ChangeSet cs, IdentifiedUser caller)
+  private void integrateIntoHistory(ChangeSet cs)
       throws IntegrationException, NoSuchChangeException,
       ResourceConflictException {
     logDebug("Beginning merge attempt on {}", cs);
@@ -531,7 +533,7 @@ public class MergeOp implements AutoCloseable {
       Multimap<Branch.NameKey, ChangeData> cbb = cs.changesByBranch();
       for (Branch.NameKey branch : cbb.keySet()) {
         OpenRepo or = openRepo(branch.getParentKey());
-        toSubmit.put(branch, validateChangeList(or, cbb.get(branch), caller));
+        toSubmit.put(branch, validateChangeList(or, cbb.get(branch)));
       }
       failFast(cs); // Done checks that don't involve running submit strategies.
 
@@ -540,7 +542,7 @@ public class MergeOp implements AutoCloseable {
         OpenBranch ob = or.getBranch(branch);
         BranchBatch submitting = toSubmit.get(branch);
         SubmitStrategy strategy = createStrategy(or, branch,
-            submitting.submitType(), ob.oldTip, caller);
+            submitting.submitType(), ob.oldTip);
         ob.mergeTip = preMerge(strategy, submitting.changes(), ob.oldTip);
       }
       checkMergeStrategyResults(cs, toSubmit.values());
@@ -556,10 +558,10 @@ public class MergeOp implements AutoCloseable {
         OpenRepo or = openRepo(project);
         for (Branch.NameKey branch : br.get(project)) {
           OpenBranch ob = or.getBranch(branch);
-          boolean updated = updateBranch(or, branch, caller);
+          boolean updated = updateBranch(or, branch);
 
           BranchBatch submitting = toSubmit.get(branch);
-          updateChangeStatus(ob, submitting.changes(), caller);
+          updateChangeStatus(ob, submitting.changes());
           updateSubmoduleSubscriptions(ob, subOp);
           if (updated) {
             fireRefUpdated(ob);
@@ -600,7 +602,7 @@ public class MergeOp implements AutoCloseable {
 
   private SubmitStrategy createStrategy(OpenRepo or,
       Branch.NameKey destBranch, SubmitType submitType,
-      CodeReviewCommit branchTip, IdentifiedUser caller)
+      CodeReviewCommit branchTip)
       throws IntegrationException, NoSuchProjectException {
     return submitStrategyFactory.create(submitType, db, or.repo, or.rw, or.ins,
         or.canMergeFlag, getAlreadyAccepted(or, branchTip), destBranch, caller,
@@ -640,8 +642,7 @@ public class MergeOp implements AutoCloseable {
   }
 
   private BranchBatch validateChangeList(OpenRepo or,
-      Collection<ChangeData> submitted, IdentifiedUser caller)
-      throws IntegrationException {
+      Collection<ChangeData> submitted) throws IntegrationException {
     logDebug("Validating {} changes", submitted.size());
     List<ChangeData> toSubmit = new ArrayList<>(submitted.size());
     Multimap<ObjectId, PatchSet.Id> revisions = getRevisions(or, submitted);
@@ -777,8 +778,8 @@ public class MergeOp implements AutoCloseable {
     }
   }
 
-  private boolean updateBranch(OpenRepo or, Branch.NameKey destBranch,
-      IdentifiedUser caller) throws IntegrationException {
+  private boolean updateBranch(OpenRepo or, Branch.NameKey destBranch)
+      throws IntegrationException {
     OpenBranch ob = or.getBranch(destBranch);
     CodeReviewCommit currentTip = ob.getCurrentTip();
     if (Objects.equals(ob.oldTip, currentTip)) {
@@ -924,8 +925,8 @@ public class MergeOp implements AutoCloseable {
     failFast(cs);
   }
 
-  private void updateChangeStatus(OpenBranch ob, List<ChangeData> submitted,
-      IdentifiedUser caller) throws ResourceConflictException {
+  private void updateChangeStatus(OpenBranch ob, List<ChangeData> submitted)
+      throws ResourceConflictException {
     List<Change.Id> problemChanges = new ArrayList<>(submitted.size());
     logDebug("Updating change status for {} changes", submitted.size());
 
@@ -940,7 +941,7 @@ public class MergeOp implements AutoCloseable {
         checkState(s != null,
             "status not set for change %s; expected to previously fail fast",
             id);
-        setApproval(cd, caller);
+        setApproval(cd);
 
         ObjectId mergeResultRev = ob.mergeTip != null
             ? ob.mergeTip.getMergeResults().get(commit) : null;
@@ -1093,18 +1094,17 @@ public class MergeOp implements AutoCloseable {
     });
   }
 
-  private void setApproval(ChangeData cd, IdentifiedUser user)
-      throws OrmException, IOException {
+  private void setApproval(ChangeData cd) throws OrmException, IOException {
     Timestamp timestamp = TimeUtil.nowTs();
     ChangeControl control = cd.changeControl();
     PatchSet.Id psId = cd.currentPatchSet().getId();
     PatchSet.Id psIdNewRev = commits.get(cd.change().getId())
         .change().currentPatchSetId();
 
-    logDebug("Add approval for " + cd + " from user " + user);
+    logDebug("Add approval for " + cd);
     ChangeUpdate update = updateFactory.create(control, timestamp);
     update.setPatchSetId(psId);
-    update.putReviewer(user.getAccountId(), REVIEWER);
+    update.putReviewer(caller.getAccountId(), REVIEWER);
     Optional<SubmitRecord> okRecord = findOkRecord(cd.getSubmitRecords());
     if (okRecord.isPresent()) {
       update.merge(ImmutableList.of(okRecord.get()));
@@ -1113,7 +1113,7 @@ public class MergeOp implements AutoCloseable {
     try {
       BatchMetaDataUpdate batch = update.openUpdate();
       LabelNormalizer.Result normalized =
-          approve(control, psId, user, update, timestamp);
+          approve(control, psId, caller, update, timestamp);
       batch.write(update, new CommitBuilder());
 
       // If the submit strategy created a new revision (rebase, cherry-pick)