Add AccountIndexRewriter

The AccountIndexRewriter only translates Predicate<AccountState> to
IndexedAccountQuery.

It is much simpler than the ChangeIndexRewriter because for the
account index there are no subindices and all predicates are served by
the index. If a predicates requires a field that is not contained in
the current index schema we would just fail those queries at the
QueryBuilder.

Change-Id: Ib0e8bcba9b475d861b102a8a7c51fcf13a3418ae
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-server/src/test/java/com/google/gerrit/server/index/change/ChangeIndexRewriterTest.java

@@ -45,13 +45,13 @@ import java.util.Arrays;
 import java.util.EnumSet;
 import java.util.Set;
 
-public class IndexRewriterTest extends GerritBaseTests {
+public class ChangeIndexRewriterTest extends GerritBaseTests {
   private static final IndexConfig CONFIG = IndexConfig.createDefault();
 
   private FakeChangeIndex index;
   private ChangeIndexCollection indexes;
   private ChangeQueryBuilder queryBuilder;
-  private IndexRewriter rewrite;
+  private ChangeIndexRewriter rewrite;
 
   @Before
   public void setUp() throws Exception {
@@ -59,7 +59,7 @@ public class IndexRewriterTest extends GerritBaseTests {
     indexes = new ChangeIndexCollection();
     indexes.setSearchIndex(index);
     queryBuilder = new FakeQueryBuilder(indexes);
-    rewrite = new IndexRewriter(indexes,
+    rewrite = new ChangeIndexRewriter(indexes,
         IndexConfig.create(0, 0, 3));
   }
 
@@ -292,6 +292,6 @@ public class IndexRewriterTest extends GerritBaseTests {
   }
 
   private Set<Change.Status> status(String query) throws QueryParseException {
-    return IndexRewriter.getPossibleStatus(parse(query));
+    return ChangeIndexRewriter.getPossibleStatus(parse(query));
   }
 }