Restructure the public API for server

pkg/analysis_server/lib/src/context_manager.dart

 // Copyright (c) 2014, 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 context.directory.manager;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:core' hide Resource;
 
+import 'package:analysis_server/plugin/analysis/resolver_provider.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/server_options.dart';
-import 'package:analysis_server/uri/resolver_provider.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/plugin/options.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
 import 'package:analyzer/source/package_map_provider.dart';
 import 'package:analyzer/source/package_map_resolver.dart';
 import 'package:analyzer/source/path_filter.dart';
 import 'package:analyzer/source/pub_package_map_provider.dart';
 import 'package:analyzer/source/sdk_ext.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 1396 matching lines @@
           var path = resourceProvider.pathContext.fromUri(uri);
           packageMap[name] = <Folder>[resourceProvider.getFolder(path)];
         }
       });
       return <UriResolver>[new SdkExtUriResolver(packageMap)];
     } else {
       return const <UriResolver>[];
     }
   }
 }