Add source kind to the incremental cache.

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 35 matching lines @@
 import 'format.dart' as generated;
 
 /**
  * Annotation describing information which is not part of Dart semantics; in
  * other words, if this information (or any information it refers to) changes,
  * static analysis and runtime behavior of the library are unaffected.
  */
 const informative = null;
 
 /**
- * Information about URIs referenced by a library.
+ * Information about a source that depends only on its content.
  */
-@TopLevel('CaLU')
-abstract class CacheLibraryUris extends base.SummaryClass {
-  factory CacheLibraryUris.fromBuffer(List<int> buffer) =>
-      generated.readCacheLibraryUris(buffer);
+@TopLevel('CaSS')
+abstract class CacheSourceContent extends base.SummaryClass {
+  factory CacheSourceContent.fromBuffer(List<int> buffer) =>
+      generated.readCacheSourceContent(buffer);
 
   /**
    * The list of exported URIs, e.g. `dart:core`, or `foo/bar.dart`,
    * or `package:foo/bar.dart`.

[Paul Berry, 2016/03/18 18:38:14]

Document what happens to this field when [kind] is CacheSourceKind.part.  (I
assume it's empty?)

[scheglov, 2016/03/18 19:42:06]

Done.

    */
-  @Id(1)
+  @Id(2)
   List<String> get exportedUris;
 
   /**
    * The list of explicitly imported URIs, e.g. `dart:core`, or `foo/bar.dart`,
    * or `package:foo/bar.dart`.

[Paul Berry, 2016/03/18 18:38:14]

Same here

[scheglov, 2016/03/18 19:42:06]

Done.

    */
+  @Id(1)
+  List<String> get importedUris;
+
+  /**
+   * The kind of the source.
+   */
   @Id(0)
-  List<String> get importedUris;
+  CacheSourceKind get kind;
 
   /**
    * The list of part URIs, e.g. `foo/bar.dart`.
    */
-  @Id(2)
+  @Id(3)
   List<String> get partUris;
 }
 
 /**
+ * Kind of a source in the cache.
+ */
+enum CacheSourceKind { library, part }
+
+/**
  * Information about an element code range.
  */
 abstract class CodeRange extends base.SummaryClass {
   /**
    * Length of the element code.
    */
   @Id(1)
   int get length;
 
   /**
@@ skipping 2329 matching lines @@
    */
   @Id(11)
   int get visibleLength;
 
   /**
    * If a local variable, the beginning of the visible range; zero otherwise.
    */
   @Id(12)
   int get visibleOffset;
 }