Improve used name relations and fields indexing.

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 206 matching lines @@
    *   Is invoked at.
    * Right: location.
    */
   IS_INVOKED_BY,
 
   /**
    * Left: any element.
    *   Is referenced (and not invoked, read/written) at.
    * Right: location.
    */
-  IS_REFERENCED_BY
+  IS_REFERENCED_BY,
+
+  /**
+   * Left: unresolved member name.
+   *   Is read at.
+   * Right: location.
+   */
+  IS_READ_BY,
+
+  /**
+   * Left: unresolved member name.
+   *   Is both read and written at.
+   * Right: location.
+   */
+  IS_READ_WRITTEN_BY,
+
+  /**
+   * Left: unresolved member name.
+   *   Is written at.
+   * Right: location.
+   */
+  IS_WRITTEN_BY
 }
 
 /**
  * When we need to reference a synthetic element in [PackageIndex] we use a
  * value of this enum to specify which kind of the synthetic element we
  * actually reference.
  */
 enum IndexSyntheticElementKind {
   /**
    * Not a synthetic element.
@@ skipping 2104 matching lines @@
    */
   @Id(11)
   int get visibleLength;
 
   /**
    * If a local variable, the beginning of the visible range; zero otherwise.
    */
   @Id(12)
   int get visibleOffset;
 }