Initial cut for a development server

lib/src/codegen/dart_codegen.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 ddc.src.codegen.dart_codegen;
 
 import 'dart:io' show File;
 
 import 'package:analyzer/analyzer.dart' as analyzer;
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 467 matching lines @@
   }
 }
 
 // This class emits the code unchanged, for comparison purposes.
 class EmptyDartGenerator extends codegenerator.CodeGenerator {
   final CompilerOptions options;
 
   EmptyDartGenerator(String outDir, Uri root, TypeRules rules, this.options)
       : super(outDir, root, rules);
 
+  void generateLibrary(Iterable<CompilationUnit> units, LibraryInfo info,
+      CheckerReporter reporter) {
+    for (var unit in units) {
+      var outputDir = makeOutputDirectory(info, unit);
+      reporter.enterSource(unit.element.source);
+      generateUnit(unit, info, outputDir);
+      reporter.leaveSource();
+    }
+  }
+
   void generateUnit(CompilationUnit unit, LibraryInfo info, String libraryDir) {
     var uri = unit.element.source.uri;
     _log.fine("Emitting original unit " + uri.toString());
     FileWriter out = new FileWriter(
         options, path.join(libraryDir, '${uri.pathSegments.last}'));
     var unitGen = new EmptyUnitGenerator(unit, out);
     unitGen.generate();
     out.finalize();
   }
 }