feat(dart/transform): Support part directives

Allow users to split libraries using the `part` directive. Closes angular#1817

Author: Tim Blasi

modules/angular2/src/core/compiler/directive_lifecycle_reflector.dart

@@ -1,3 +1,5 @@
+library angular2.src.core.compiler.directive_lifecycle_reflector;
+
 import 'package:angular2/src/core/annotations_impl/annotations.dart';
 import 'package:angular2/src/core/compiler/interfaces.dart';
 import 'package:angular2/src/reflection/reflection.dart';

modules/angular2/src/test_lib/test_lib.dart

@@ -100,7 +100,8 @@ class Expect extends gns.Expect {
  void toThrowError([message = ""]) => toThrowWith(message: message);
  void toThrowErrorWith(message) => expectException(this.actual, message);
  void toBePromise() => gns.guinness.matchers.toBeTrue(actual is Future);
- void toHaveCssClass(className) => gns.guinness.matchers.toBeTrue(DOM.hasClass(actual, className));
+ void toHaveCssClass(className) =>
+ gns.guinness.matchers.toBeTrue(DOM.hasClass(actual, className));
  void toImplement(expected) => toBeA(expected);
  void toBeNaN() =>
  gns.guinness.matchers.toBeTrue(double.NAN.compareTo(actual) == 0);
@@ -139,7 +140,8 @@ class NotExpect extends gns.NotExpect {
 
  void toEqual(expected) => toHaveSameProps(expected);
  void toBePromise() => gns.guinness.matchers.toBeFalse(actual is Future);
- void toHaveCssClass(className) => gns.guinness.matchers.toBeFalse(DOM.hasClass(actual, className));
+ void toHaveCssClass(className) =>
+ gns.guinness.matchers.toBeFalse(DOM.hasClass(actual, className));
  void toBeNull() => gns.guinness.matchers.toBeFalse(actual == null);
  Function get _expect => gns.guinness.matchers.expect;
 }

modules/angular2/src/transform/common/async_string_writer.dart

@@ -16,7 +16,7 @@ class AsyncStringWriter extends PrintWriter {
  : _curr = curr,
  _bufs = <StringBuffer>[curr];
 
- AsyncStringWriter() : this._(new StringBuffer());
+ AsyncStringWriter([Object content = ""]) : this._(new StringBuffer(content));
 
  void print(x) {
  _curr.write(x);