Store index into AnalysisDriverResolvedUnit and return in AnalysisResult.

pkg/analyzer/lib/src/summary/idl.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.
 
 /**
  * This file is an "idl" style description of the summary format.  It
  * contains abstract classes which declare the interface for reading data from
  * summaries.  It is parsed and transformed into code that implements the
  * summary format.
  *
@@ skipping 52 matching lines @@
 @TopLevel('ADRU')
 abstract class AnalysisDriverResolvedUnit extends base.SummaryClass {
   factory AnalysisDriverResolvedUnit.fromBuffer(List<int> buffer) =>
       generated.readAnalysisDriverResolvedUnit(buffer);
 
   /**
    * The full list of analysis errors, both syntactic and semantic.
    */
   @Id(0)
   List<AnalysisDriverUnitError> get errors;
+
+  /**
+   * The index of the unit.
+   */
+  @Id(1)
+  AnalysisDriverUnitIndex get index;
 }
 
 /**
  * Information about an error in a resolved unit.
  */
 abstract class AnalysisDriverUnitError extends base.SummaryClass {
   /**
    * The optional correction hint for the error.
    */
   @Id(4)
@@ skipping 2967 matching lines @@
   @Id(11)
   int get visibleLength;
 
   /**
    * If a local variable, the beginning of the visible range; zero otherwise.
    */
   @informative
   @Id(12)
   int get visibleOffset;
 }