Fixing websql_test after streams change.

tests/html/websql_test.dart

 library WebDBTest;
 import 'dart:async';
 import 'dart:html';
 import 'dart:web_sql';
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_individual_config.dart';
 
 void fail(message) {
   guardAsync(() {
       expect(false, isTrue, reason: message);
     });
 }
 
 Future<SqlTransaction> transaction(SqlDatabase db) {
-  final completer = new Completer<SqlTransaction>();
+  final completer = new Completer<SqlTransaction>.sync();
 
   db.transaction((SqlTransaction transaction) {
     completer.complete(transaction);
   }, (SqlError error) {
     completer.completeError(error);
   });
 
   return completer.future;
 }
 
 Future<SqlResultSet> createTable(SqlTransaction transaction, String tableName,
     String columnName) {
-  final completer = new Completer<SqlResultSet>();
+  final completer = new Completer<SqlResultSet>.sync();
 
   final sql = 'CREATE TABLE $tableName ($columnName)';
   transaction.executeSql(sql, [],
     (SqlTransaction tx, SqlResultSet rs) {
       completer.complete(rs);
     },
     (SqlTransaction tx, SqlError error) {
       completer.completeError(error);
     });
 
   return completer.future;
 }
 
 Future<SqlResultSet> insert(SqlTransaction transaction, String tableName,
     String columnName, value) {
-  final completer = new Completer<SqlResultSet>();
+  final completer = new Completer<SqlResultSet>.sync();
 
   final sql = 'INSERT INTO $tableName ($columnName) VALUES (?)';
   transaction.executeSql(sql, [value],
     (SqlTransaction tx, SqlResultSet rs) {
       completer.complete(rs);
     },
     (SqlTransaction tx, SqlError error) {
       completer.completeError(error);
     });
 
   return completer.future;
 }
 
 Future<SqlResultSet> queryTable(SqlTransaction transaction, String tableName) {
-  final completer = new Completer<SqlResultSet>();
+  final completer = new Completer<SqlResultSet>.sync();
 
   final sql = 'SELECT * FROM $tableName';
   transaction.executeSql(sql, [],
     (SqlTransaction tx, SqlResultSet rs) {
       completer.complete(rs);
     },
     (SqlTransaction tx, SqlError error) {
       completer.completeError(error);
     });
 
   return completer.future;
 }
 
 Future<SqlResultSet> dropTable(SqlTransaction transaction, String tableName,
     [bool ignoreFailure = false]) {
-  final completer = new Completer<SqlResultSet>();
+  final completer = new Completer<SqlResultSet>.sync();
 
   final sql = 'DROP TABLE $tableName';
   transaction.executeSql(sql, [],
     (SqlTransaction tx, SqlResultSet rs) {
       completer.complete(rs);
     },
     (SqlTransaction tx, SqlError error) {
       if (ignoreFailure) {
         completer.complete(null);
       } else {
@@ skipping 52 matching lines @@
         var row = resultSet.rows.item(0);
         expect(row.containsKey(columnName), isTrue);
         expect(row[columnName], 'Some text data');
         expect(resultSet.rows[0], row);
       }).then((_) {
         return dropTable(tx, tableName);
       });
     });
   });
 }