Don't rewrite queries when filtering project watches

In the context of ProjectWatch, ChangeQueryRewriter may be bound to an
index-based rewriter. The current implementation of the index rewriter
may call getSource() during the course of rewriting, possibly kicking
off an async query. However, for the purpose of watches, we only ever
call match() on the predicate; we never need to actually enumerate the
results.

Don't bother rewriting the predicates; the rewriter is about querying
the database more efficiently, but all we're doing is evaluating the
predicate on a change. It is likely that the cost of applying the
rewrite algorithm outweighs any benefit of using a simplified
predicate tree.

Change-Id: I3a6e867305b0e1e4956ccdee8113827b04e63580

gerrit-server/src/main/java/com/google/gerrit/server/mail/EmailArguments.java

@@ -30,7 +30,6 @@ import com.google.gerrit.server.patch.PatchListCache;
 import com.google.gerrit.server.patch.PatchSetInfoFactory;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.query.change.ChangeQueryBuilder;
-import com.google.gerrit.server.query.change.ChangeQueryRewriter;
 import com.google.gerrit.server.ssh.SshAdvertisedAddresses;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
@@ -60,7 +59,6 @@ class EmailArguments {
   final List<String> sshAddresses;
 
   final ChangeQueryBuilder.Factory queryBuilder;
-  final Provider<ChangeQueryRewriter> queryRewriter;
   final Provider<ReviewDb> db;
   final RuntimeInstance velocityRuntime;
   final EmailSettings settings;
@@ -78,7 +76,7 @@ class EmailArguments {
       @CanonicalWebUrl @Nullable Provider<String> urlProvider,
       AllProjectsName allProjectsName,
       ChangeQueryBuilder.Factory queryBuilder,
-      Provider<ChangeQueryRewriter> queryRewriter, Provider<ReviewDb> db,
+      Provider<ReviewDb> db,
       RuntimeInstance velocityRuntime,
       EmailSettings settings,
       @SshAdvertisedAddresses List<String> sshAddresses) {
@@ -98,7 +96,6 @@ class EmailArguments {
     this.urlProvider = urlProvider;
     this.allProjectsName = allProjectsName;
     this.queryBuilder = queryBuilder;
-    this.queryRewriter = queryRewriter;
     this.db = db;
     this.velocityRuntime = velocityRuntime;
     this.settings = settings;

gerrit-server/src/main/java/com/google/gerrit/server/mail/ProjectWatch.java

@@ -209,7 +209,6 @@ public class ProjectWatch {
       } else {
         p = Predicate.and(filterPredicate, p);
       }
-      p = args.queryRewriter.get().rewrite(p);
     }
     return p == null ? true : p.match(changeData);
   }