RebaseIfNecessary: Don't overwrite committer ident

It was necessary to explicitly set this prior to the BatchUpdate
migration, but now the committer is implied by the update context, so
overwriting it is not necessary.

Change-Id: Ibcc872aac9f751659c26bcb9ca2d994c02a05da5

gerrit-server/src/main/java/com/google/gerrit/server/git/strategy/RebaseIfNecessary.java

@@ -37,7 +37,6 @@ import com.google.gerrit.server.project.NoSuchChangeException;
 import com.google.gwtorm.server.OrmException;
 
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.PersonIdent;
 
 import java.io.IOException;
 import java.util.Collection;
@@ -54,12 +53,6 @@ public class RebaseIfNecessary extends SubmitStrategy {
     this.newCommits = new HashMap<>();
   }
 
-  private PersonIdent getSubmitterIdent() {
-    return args.caller.newCommitterIdent(
-        args.serverIdent.getWhen(),
-        args.serverIdent.getTimeZone());
-  }
-
   @Override
   public MergeTip run(final CodeReviewCommit branchTip,
       final Collection<CodeReviewCommit> toMerge) throws IntegrationException {
@@ -163,7 +156,6 @@ public class RebaseIfNecessary extends SubmitStrategy {
             // Racy read of patch set is ok; see comments in RebaseChangeOp.
             args.db.patchSets().get(toMerge.getPatchsetId()),
             mergeTip.getCurrentTip().name())
-          .setCommitterIdent(getSubmitterIdent())
           .setRunHooks(false)
           .setValidatePolicy(CommitValidators.Policy.NONE);
       try {