Make full_emitter parts into libraries

pkg/compiler/lib/src/js_emitter/full_emitter/nsm_emitter.dart

 // Copyright (c) 2013, 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.
 
-part of dart2js.js_emitter.full_emitter;
+library dart2js.js_emitter.full_emitter.nsm_emitter;
+
+import '../../elements/elements.dart'
+    show
+    ClassElement,
+    MemberElement;
+import '../../js/js.dart' as jsAst;
+import '../../js/js.dart' show js;
+import '../../js_backend/js_backend.dart'
+    show
+    GetterName,
+    SetterName;
+import '../../universe/selector.dart' show Selector;
+import '../../util/characters.dart' show $$, $A, $HASH, $Z, $a, $z;
+import '../../world.dart' show ClosedWorld;
+import '../js_emitter.dart' hide Emitter, EmitterFactory;
+import '../model.dart';
+import 'emitter.dart';
 
 class NsmEmitter extends CodeEmitterHelper {
   final ClosedWorld closedWorld;
   final List<Selector> trivialNsmHandlers = <Selector>[];
 
   NsmEmitter(this.closedWorld);
 
   /// If this is true then we can generate the noSuchMethod handlers at startup
   /// time, instead of them being emitted as part of the Object class.
   bool get generateTrivialNsmHandlers => true;
@@ skipping 375 matching lines @@
   }
 
   String get value {
     if (_cachedValue == null) {
       _cachedValue = _computeDiffEncoding();
     }
 
     return _cachedValue;
   }
 }