Use SdkExtensionFinder in the old Analysis Server implementation.

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;
@@ skipping 1692 matching lines @@
   Packages get packages => null;
 
   @override
   Iterable<UriResolver> createPackageUriResolvers(
           ResourceProvider resourceProvider) =>
       <UriResolver>[resolver];
 
   @override
   EmbedderYamlLocator getEmbedderLocator(ResourceProvider resourceProvider) =>
       new EmbedderYamlLocator(null);
+
+  @override
+  SdkExtensionFinder getSdkExtensionFinder(ResourceProvider resourceProvider) =>
+      new SdkExtensionFinder(null);
 }
 
 /**
  * An instance of the class [FolderDisposition] represents the information
  * gathered by the [ContextManagerImpl] to determine how to create an
  * [AnalysisContext] for a given folder.
  *
  * Note: [ContextManagerImpl] may use equality testing and hash codes to
  * determine when two folders should share the same context, so derived classes
  * may need to override operator== and hashCode() if object identity is
@@ skipping 27 matching lines @@
    */
   Iterable<UriResolver> createPackageUriResolvers(
       ResourceProvider resourceProvider);
 
   /**
    * Return the locator used to locate the _embedder.yaml file used to configure
    * the SDK. The [resourceProvider] is used to access the file system in cases
    * where that is necessary.
    */
   EmbedderYamlLocator getEmbedderLocator(ResourceProvider resourceProvider);
+
+  /**
+   * Return the extension finder used to locate the `_sdkext` file used to add
+   * extensions to the SDK. The [resourceProvider] is used to access the file
+   * system in cases where that is necessary.
+   */
+  SdkExtensionFinder getSdkExtensionFinder(ResourceProvider resourceProvider);
 }
 
 /**
  * Concrete [FolderDisposition] object indicating that the context for a given
  * folder should not resolve "package:" URIs at all.
  */
 class NoPackageFolderDisposition extends FolderDisposition {
   @override
   final String packageRoot;
 
   NoPackageFolderDisposition({this.packageRoot});
 
   @override
   Packages get packages => null;
 
   @override
   Iterable<UriResolver> createPackageUriResolvers(
           ResourceProvider resourceProvider) =>
       const <UriResolver>[];
 
   @override
   EmbedderYamlLocator getEmbedderLocator(ResourceProvider resourceProvider) =>
       new EmbedderYamlLocator(null);
+
+  @override
+  SdkExtensionFinder getSdkExtensionFinder(ResourceProvider resourceProvider) =>
+      new SdkExtensionFinder(null);
 }
 
 /**
  * Concrete [FolderDisposition] object indicating that the context for a given
  * folder should resolve packages using a package map.
  */
 class PackageMapDisposition extends FolderDisposition {
   final Map<String, List<Folder>> packageMap;
 
   EmbedderYamlLocator _embedderLocator;
+  SdkExtensionFinder _sdkExtensionFinder;
 
   @override
   final String packageRoot;
 
   PackageMapDisposition(this.packageMap, {this.packageRoot});
 
   @override
   Packages get packages => null;
 
   @override
   Iterable<UriResolver> createPackageUriResolvers(
           ResourceProvider resourceProvider) =>
       <UriResolver>[
         new SdkExtUriResolver(packageMap),
         new PackageMapUriResolver(resourceProvider, packageMap)
       ];
 
   @override
   EmbedderYamlLocator getEmbedderLocator(ResourceProvider resourceProvider) {
     if (_embedderLocator == null) {
       _embedderLocator = new EmbedderYamlLocator(packageMap);
     }
     return _embedderLocator;
   }
+
+  @override
+  SdkExtensionFinder getSdkExtensionFinder(ResourceProvider resourceProvider) {
+    return _sdkExtensionFinder ??= new SdkExtensionFinder(packageMap);
+  }
 }
 
 /**
  * Concrete [FolderDisposition] object indicating that the context for a given
  * folder should resolve packages using a ".packages" file.
  */
 class PackagesFileDisposition extends FolderDisposition {
   @override
   final Packages packages;
 
   Map<String, List<Folder>> packageMap;
 
   EmbedderYamlLocator _embedderLocator;
+  SdkExtensionFinder _sdkExtensionFinder;
 
   PackagesFileDisposition(this.packages);
 
   @override
   String get packageRoot => null;
 
   Map<String, List<Folder>> buildPackageMap(ResourceProvider resourceProvider) {
     if (packageMap == null) {
       packageMap = <String, List<Folder>>{};
       if (packages != null) {
@@ skipping 21 matching lines @@
   }
 
   @override
   EmbedderYamlLocator getEmbedderLocator(ResourceProvider resourceProvider) {
     if (_embedderLocator == null) {
       _embedderLocator =
           new EmbedderYamlLocator(buildPackageMap(resourceProvider));
     }
     return _embedderLocator;
   }
+
+  @override
+  SdkExtensionFinder getSdkExtensionFinder(ResourceProvider resourceProvider) {
+    return _sdkExtensionFinder ??=
+        new SdkExtensionFinder(buildPackageMap(resourceProvider));
+  }
 }