Explicitly remove AnalysisContext from ContextCodec.

pkg/analysis_server/lib/src/index/split_store.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 index.split.store;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:io';
 import 'dart:typed_data';
@@ skipping 17 matching lines @@
   Map<AnalysisContext, int> _contextToIndex = new HashMap<AnalysisContext, int>(
       );
 
   /**
    * A table mapping indices to the corresponding contexts.
    */
   Map<int, AnalysisContext> _indexToContext = new HashMap<int, AnalysisContext>(
       );
 
   /**
+   * The next id to assign.
+   */
+  int _nextId = 0;
+
+  /**
    * Returns the [AnalysisContext] that corresponds to the given index.
    */
   AnalysisContext decode(int index) => _indexToContext[index];
 
   /**
    * Returns an unique index for the given [AnalysisContext].
    */
   int encode(AnalysisContext context) {
     int index = _contextToIndex[context];
     if (index == null) {
-      index = _indexToContext.length;
+      index = _nextId++;
       _contextToIndex[context] = index;
       _indexToContext[index] = context;
     }
     return index;
   }
+
+  /**
+   * Removes the given [context].
+   */
+  void remove(AnalysisContext context) {
+    int id = _contextToIndex.remove(context);
+    if (id != null) {
+      _indexToContext.remove(id);
+    }
+  }
 }
 
 
 /**
  * A helper that encodes/decodes [Element]s to/from integers.
  */
 class ElementCodec {
   /**
    * A list that works as a mapping of integers to element encodings (in form of integer arrays).
    */
@@ skipping 833 matching lines @@
     context = _unwrapContext(context);
     if (context == null) {
       return;
     }
     // remove sources
     removeSources(context, null);
     // remove context information
     _contextToLibraryToUnits.remove(context);
     _contextToUnitToLibraries.remove(context);
     _contextNodeRelations.remove(_contextCodec.encode(context));
+    // remove context from codec
+    _contextCodec.remove(context);
   }
 
   @override
   void removeSource(AnalysisContext context, Source source) {
     context = _unwrapContext(context);
     if (context == null) {
       return;
     }
     // remove nodes for unit/library pairs
     Map<Source, Set<Source>> unitToLibraries =
@@ skipping 224 matching lines @@
     return new Uint8List.fromList(_buffer.takeBytes());
   }
 
   void writeInt(int value) {
     _buffer.addByte((value & 0xFF000000) >> 24);
     _buffer.addByte((value & 0x00FF0000) >> 16);
     _buffer.addByte((value & 0x0000FF00) >> 8);
     _buffer.addByte(value & 0xFF);
   }
 }