Add missing results needed to convert AnalysisContext to the new task model

pkg/analyzer/lib/task/dart.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.task.dart;
 
 import 'package:analyzer/src/generated/ast.dart';
+import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/task/model.dart';
 
 /**
  * The analysis errors associated with a target.
  *
  * The value combines errors represented by multiple other results.
  */
@@ skipping 39 matching lines @@
  *
  * The list will be empty if there are no parts, but will not be `null`. The
  * list does *not* include the source for the defining compilation unit.
  *
  * The result is only available for targets representing a Dart library.
  */
 final ListResultDescriptor<Source> INCLUDED_PARTS =
     new ListResultDescriptor<Source>('INCLUDED_PARTS', Source.EMPTY_ARRAY);
 
 /**
+ * A flag specifying whether a library is dependent on code that is only
+ * available in a client.
+ *
+ * The result is only available for targets representing a Dart library.
+ */
+final ResultDescriptor<bool> IS_CLIENT =
+    new ResultDescriptor<bool>('IS_CLIENT', false);
+
+/**
  * A flag specifying whether a library is launchable.
  *
  * The result is only available for targets representing a Dart library.
  */
 final ResultDescriptor<bool> IS_LAUNCHABLE =
     new ResultDescriptor<bool>('IS_LAUNCHABLE', false);
 
 /**
+ * The fully built [LibraryElement] associated with a library.
+ *
+ * The result is only available for targets representing a Dart library.
+ */
+final ResultDescriptor<LibraryElement> LIBRARY_ELEMENT =
+    new ResultDescriptor<LibraryElement>('LIBRARY_ELEMENT', null);
+
+/**
  * The compilation unit AST produced while parsing a compilation unit.
  *
  * The AST structure will not have resolution information associated with it.
  *
  * The result is only available for targets representing a Dart compilation unit.
  */
 final ResultDescriptor<CompilationUnit> PARSED_UNIT =
     new ResultDescriptor<CompilationUnit>('PARSED_UNIT', null);
 
 /**
@@ skipping 18 matching lines @@
 /**
  * The sources of the Dart files that a library consists of.
  *
  * The list will include the source of the defining unit and [INCLUDED_PARTS].
  * So, it is never empty or `null`.
  *
  * The result is only available for targets representing a Dart library.
  */
 final ListResultDescriptor<Source> UNITS =
     new ListResultDescriptor<Source>('UNITS', Source.EMPTY_ARRAY);