Increase AST cache size to improve performance for large projects

pkg/analyzer/lib/src/task/dart.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.task.dart;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 28 matching lines @@
 import 'package:analyzer/src/task/strong/checker.dart';
 import 'package:analyzer/src/task/strong_mode.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
 
 /**
  * The [ResultCachingPolicy] for ASTs.
  */
 const ResultCachingPolicy AST_CACHING_POLICY =
-    const SimpleResultCachingPolicy(8192, 8192);
+    const SimpleResultCachingPolicy(16384, 16384);
 
 /**
  * The [ResultCachingPolicy] for [Element]s.
  */
 const ResultCachingPolicy ELEMENT_CACHING_POLICY =
     const SimpleResultCachingPolicy(-1, -1);
 
 /**
  * The [ResultCachingPolicy] for [TOKEN_STREAM].
  */
@@ skipping 5294 matching lines @@
 
   @override
   bool moveNext() {
     if (_newSources.isEmpty) {
       return false;
     }
     currentTarget = _newSources.removeLast();
     return true;
   }
 }