Fix for opening SDK sources.

pkg/analysis_server/lib/src/analysis_server.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 analysis.server;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/file_system/file_system.dart';
@@ skipping 11 matching lines @@
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analysis_services/constants.dart';
 import 'package:analysis_services/index/index.dart';
 import 'package:analysis_services/search/search_engine.dart';
 import 'package:analyzer/src/generated/element.dart';
+import 'package:path/path.dart';
 
 
 class AnalysisServerContextDirectoryManager extends ContextDirectoryManager {
   final AnalysisServer analysisServer;
 
   /**
    * The default options used to create new analysis contexts.
    */
   AnalysisOptionsImpl defaultOptions = new AnalysisOptionsImpl();
 
@@ skipping 487 matching lines @@
     });
     // remember new subscriptions
     this.analysisServices = subscriptions;
   }
 
   /**
    * Return the [AnalysisContext] that is used to analyze the given [path].
    * Return `null` if there is no such context.
    */
   AnalysisContext getAnalysisContext(String path) {
+    // try to find a containing context
     for (Folder folder in folderMap.keys) {
       if (path.startsWith(folder.path)) {
         return folderMap[folder];
       }
     }
+    // check if there is a context that analyzed this source
+    {
+      Source source = getSource(path);
+      for (AnalysisContext context in folderMap.values) {
+        SourceKind kind = context.getKindOf(source);
+        if (kind != null) {
+          return context;
+        }
+      }
+    }
     return null;
   }
 
   /**
    * Return the [Source] of the Dart file with the given [path].
    */
   Source getSource(String path) {
+    // try SDK
+    {
+      Uri uri = toUri(path);
+      Source sdkSource = defaultSdk.fromFileUri(uri);
+      if (sdkSource != null) {
+        return sdkSource;
+      }
+    }
+    // file-based source
     File file = contextDirectoryManager.resourceProvider.getResource(path);
     return file.createSource();
   }
 
   /**
    * Returns the [CompilationUnit] of the Dart file with the given [path] that
    * should be used to resend notifications for already resolved unit.
    * Returns `null` if the file is not a part of any context, library has not
    * been yet resolved, or any problem happened.
    */
@@ skipping 229 matching lines @@
 /**
  * An enumeration of the services provided by the server domain.
  */
 class ServerService extends Enum2<ServerService> {
   static const ServerService STATUS = const ServerService('STATUS', 0);
 
   static const List<ServerService> VALUES = const [STATUS];
 
   const ServerService(String name, int ordinal) : super(name, ordinal);
 }