Revert "Use single InputPackagesResultProvider, without SdkSummaryResultProvider."

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

 // Copyright (c) 2015, 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;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 186 matching lines @@
    * not) being implicitly analyzed.
    */
   StreamController<ImplicitAnalysisEvent> _implicitAnalysisEventsController;
 
   /**
    * The listeners that are to be notified when various analysis results are
    * produced in this context.
    */
   List<AnalysisListener> _listeners = new List<AnalysisListener>();
 
-  /**
-   * Determines whether this context should attempt to make use of the global
-   * SDK cache partition. Note that if this context is responsible for
-   * resynthesizing the SDK element model, this flag should be set to `false`,
-   * so that resynthesized elements belonging to this context won't leak into
-   * the global SDK cache partition.
-   */
-  bool useSdkCachePartition = true;
-
   @override
   ResultProvider resultProvider;
 
   /**
    * The map of [ResultChangedEvent] controllers.
    */
   final Map<ResultDescriptor, StreamController<ResultChangedEvent>>
       _resultChangedControllers =
       <ResultDescriptor, StreamController<ResultChangedEvent>>{};
 
@@ skipping 515 matching lines @@
   }
 
   /**
    * Create an analysis cache based on the given source [factory].
    */
   AnalysisCache createCacheFromSourceFactory(SourceFactory factory) {
     AnalysisCache createCache() {
       if (factory == null) {
         return new AnalysisCache(<CachePartition>[_privatePartition]);
       }
-      if (!useSdkCachePartition) {
-        return new AnalysisCache(<CachePartition>[_privatePartition]);
-      }
       DartSdk sdk = factory.dartSdk;
       if (sdk == null) {
         return new AnalysisCache(<CachePartition>[_privatePartition]);
       }
       return new AnalysisCache(<CachePartition>[
         AnalysisEngine.instance.partitionManager.forSdk(sdk),
         _privatePartition
       ]);
     }
 
@@ skipping 1512 matching lines @@
     }
     DartSdk sdk = factory.dartSdk;
     if (sdk == null) {
       throw new ArgumentError(
           "The source factory for an SDK analysis context must have a DartUriResolver");
     }
     return new AnalysisCache(
         <CachePartition>[AnalysisEngine.instance.partitionManager.forSdk(sdk)]);
   }
 }