Add initial support for parts to the incremental kernel generator.

pkg/front_end/lib/incremental_resolved_ast_generator.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:async';
 
 import 'package:front_end/src/base/processed_options.dart';
 import 'package:front_end/src/incremental_resolved_ast_generator_impl.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 
@@ skipping 14 matching lines @@
 /// TODO(paulberry): add information about libraries that were removed.
 }
 
 /// Represents the resolved ASTs for all the compilation units in a single
 /// library.
 ///
 /// Not intended to be implemented or extended by clients.
 class ResolvedLibrary {
   final CompilationUnit definingCompilationUnit;
 
-  ResolvedLibrary(this.definingCompilationUnit);
+  final Map<Uri, CompilationUnit> partUnits;
 
-  // TODO(paulberry): add support for parts.
+  ResolvedLibrary(this.definingCompilationUnit, this.partUnits);
 }
 
 /// Interface for generating an initial resolved representation of a program and
 /// keeping it up to date as incremental changes are made.
 ///
 /// This class maintains an internal "previous program state"; each
 /// time [computeDelta] is called, it updates the previous program state and
 /// produces a representation of what has changed.  When there are few changes,
 /// a call to [computeDelta] should be much faster than compiling the whole
 /// program from scratch.
@@ skipping 47 matching lines @@
 
   /// Remove all source files from the set of valid sources.  This guarantees
   /// that all files will be re-read on the next call to [computeDelta].
   ///
   /// Note that this does not erase the previous program state; the next time
   /// [computeDelta] is called, if parts of the program are discovered to be
   /// unchanged, parts of the previous program state will still be re-used to
   /// speed up compilation.
   void invalidateAll();
 }