Remove unused code from limited invalidation.

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 1853 matching lines @@
           if (oldUnit != null) {
             CompilationUnit newUnit = parseCompilationUnit(source);
             IncrementalCompilationUnitElementBuilder builder =
                 new IncrementalCompilationUnitElementBuilder(oldUnit, newUnit);
             builder.build();
             CompilationUnitElementDelta unitDelta = builder.unitDelta;
             if (!unitDelta.hasDirectiveChange) {
               unitEntry.setValueIncremental(
                   COMPILATION_UNIT_CONSTANTS, builder.unitConstants, false);
               DartDelta dartDelta = new DartDelta(source);
-              dartDelta.hasDirectiveChange = unitDelta.hasDirectiveChange;
               unitDelta.addedDeclarations.forEach(dartDelta.elementChanged);
               unitDelta.removedDeclarations.forEach(dartDelta.elementChanged);
               unitDelta.classDeltas.values.forEach(dartDelta.classChanged);
-              // Add other names in the library that are changed transitively.
-              {
-                ReferencedNames referencedNames = new ReferencedNames(source);
-                new ReferencedNamesBuilder(referencedNames).build(oldUnit);
-                dartDelta.addChangedElements(referencedNames, librarySource);
-              }
-              // Invalidate using the prepared DartDelta.
               entry.setState(CONTENT, CacheState.INVALID, delta: dartDelta);
               return;
             }
           }
         }
       }
       entry.setState(CONTENT, CacheState.INVALID);
       entry.setState(MODIFICATION_TIME, CacheState.INVALID);
       entry.setState(SOURCE_KIND, CacheState.INVALID);
     }
@@ skipping 407 matching lines @@
     }
     DartSdk sdk = factory.dartSdk;
     if (sdk == null) {
       throw new IllegalArgumentException(
           "The source factory for an SDK analysis context must have a DartUriResolver");
     }
     return new AnalysisCache(
         <CachePartition>[AnalysisEngine.instance.partitionManager.forSdk(sdk)]);
   }
 }