Fix for opening SDK sources.

pkg/analysis_services/lib/src/correction/fix.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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library services.src.correction.fix;
 
 import 'dart:collection';
@@ skipping 32 matching lines @@
  */
 class FixProcessor {
   static const int MAX_LEVENSHTEIN_DISTANCE = 3;
 
   final SearchEngine searchEngine;
   final Source source;
   final String file;
   final CompilationUnit unit;
   final AnalysisError error;
   CompilationUnitElement unitElement;
+  Source unitSource;
   LibraryElement unitLibraryElement;
   String unitLibraryFile;
   String unitLibraryFolder;
 
   final List<Edit> edits = <Edit>[];
   final Map<String, LinkedEditGroup> linkedPositionGroups = <String,
       LinkedEditGroup>{};
   Position exitPosition = null;
   final List<Fix> fixes = <Fix>[];
 
   CorrectionUtils utils;
   int errorOffset;
   int errorLength;
   int errorEnd;
   AstNode node;
   AstNode coveredNode;
 
   FixProcessor(this.searchEngine, this.source, this.file, this.unit, this.error)
       {
     unitElement = unit.element;
+    unitSource = unitElement.source;
     unitLibraryElement = unitElement.library;
     unitLibraryFile = unitLibraryElement.source.fullName;
     unitLibraryFolder = dirname(unitLibraryFile);
   }
 
   DartType get coreTypeBool => _getCoreType("bool");
 
   /**
    * Returns the EOL to use for this [CompilationUnit].
    */
@@ skipping 686 matching lines @@
         return;
       }
     }
     // check SDK libraries
     AnalysisContext context = unitLibraryElement.context;
     {
       DartSdk sdk = context.sourceFactory.dartSdk;
       List<SdkLibrary> sdkLibraries = sdk.sdkLibraries;
       for (SdkLibrary sdkLibrary in sdkLibraries) {
         SourceFactory sdkSourceFactory = context.sourceFactory;
-        String libraryUri = sdkLibrary.shortName;
-        Source librarySource = sdkSourceFactory.resolveUri(null, libraryUri);
+        String libraryUri = 'dart:' + sdkLibrary.shortName;
+        Source librarySource =
+            sdkSourceFactory.resolveUri(unitSource, libraryUri);
         // prepare LibraryElement
         LibraryElement libraryElement =
             context.getLibraryElement(librarySource);
         if (libraryElement == null) {
           continue;
         }
         // prepare exported Element
         Element element = getExportedElement(libraryElement, name);
         if (element == null) {
           continue;
@@ skipping 1112 matching lines @@
 /**
  * Describes the location for a newly created [ConstructorDeclaration].
  */
 class _ConstructorLocation {
   final String _prefix;
   final int _offset;
   final String _suffix;
 
   _ConstructorLocation(this._prefix, this._offset, this._suffix);
 }