Move byte_store.dart and file_byte_store.dart to their own subdirectory.

pkg/analyzer/lib/src/context/builder.dart

 // Copyright (c) 2016, 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.context.context_builder;
 
 import 'dart:collection';
 import 'dart:core';
 
 import 'package:analyzer/context/context_root.dart';
@@ skipping 16 matching lines @@
 import 'package:analyzer/src/generated/gn.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/workspace.dart';
 import 'package:analyzer/src/lint/registry.dart';
 import 'package:analyzer/src/services/lint.dart';
 import 'package:analyzer/src/summary/summary_sdk.dart';
 import 'package:analyzer/src/task/options.dart';
 import 'package:args/args.dart';
 import 'package:front_end/src/base/performace_logger.dart';
-import 'package:front_end/src/incremental/byte_store.dart';
+import 'package:front_end/src/byte_store/byte_store.dart';
 import 'package:package_config/packages.dart';
 import 'package:package_config/packages_file.dart';
 import 'package:package_config/src/packages_impl.dart';
 import 'package:path/src/context.dart';
 import 'package:yaml/yaml.dart';
 
 /**
  * A utility class used to build an analysis context for a given directory.
  *
  * The construction of analysis contexts is as follows:
@@ skipping 795 matching lines @@
       throw new ArgumentError('not absolute: $path');
     }
     path = context.normalize(path);
     Resource resource = provider.getResource(path);
     if (resource is File) {
       path = resource.parent.path;
     }
     return new _BasicWorkspace._(provider, path, builder);
   }
 }