Split scannerlib.dart into several libraries.

pkg/compiler/lib/src/scanner/diet_parser_task.dart

Index: pkg/compiler/lib/src/scanner/diet_parser_task.dart
diff --git a/pkg/compiler/lib/src/scanner/diet_parser_task.dart b/pkg/compiler/lib/src/scanner/diet_parser_task.dart
new file mode 100644
index 0000000000000000000000000000000000000000..ec60a2df0c87cc2dad200a01085cd0c3f855bba3
--- /dev/null
+++ b/pkg/compiler/lib/src/scanner/diet_parser_task.dart
@@ -0,0 +1,41 @@
+// 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 dart2js.parser.diet.task;
+
+import '../common/tasks.dart' show
+    CompilerTask;
+import '../compiler.dart' show
+    Compiler;
+import '../elements/elements.dart' show
+    CompilationUnitElement;
+import '../diagnostics/invariant.dart' show
+    invariant;
+
+import 'listener.dart' show
+    ElementListener,
+    ParserError;
+import 'partial_parser.dart' show
+    PartialParser;
+import 'token.dart' show
+    Token;
+
+class DietParserTask extends CompilerTask {
+  DietParserTask(Compiler compiler) : super(compiler);
+  final String name = 'Diet Parser';
+
+  dietParse(CompilationUnitElement compilationUnit, Token tokens) {
+    measure(() {
+      Function idGenerator = compiler.getNextFreeClassId;
+      ElementListener listener =
+          new ElementListener(compiler, compilationUnit, idGenerator);
+      PartialParser parser = new PartialParser(listener);
+      try {
+        parser.parseUnit(tokens);
+      } on ParserError catch(_) {
+        assert(invariant(compilationUnit, compiler.compilationFailed));
+      }
+    });
+  }
+}