dart2js: support tear-offs in the startup emitter.

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

 // Copyright (c) 2014, 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.js_emitter.full_emitter;
 
 import 'dart:convert';
 import 'dart:collection' show HashMap;
 
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
@@ skipping 186 matching lines @@
   }
 
   /// Erases the precompiled information for csp mode for all output units.
   /// Used by the incremental compiler.
   void clearCspPrecompiledNodes() {
     _cspPrecompiledFunctions.clear();
     _cspPrecompiledConstructorNames.clear();
   }
 
   @override
+  String get patchVersion => "full";
+
+  @override
   bool isConstantInlinedOrAlreadyEmitted(ConstantValue constant) {
     if (constant.isFunction) return true;    // Already emitted.
     if (constant.isPrimitive) return true;   // Inlined.
     if (constant.isDummy) return true;       // Inlined.
     // The name is null when the constant is already a JS constant.
     // TODO(floitsch): every constant should be registered, so that we can
     // share the ones that take up too much space (like some strings).
     if (namer.constantName(constant) == null) return true;
     return false;
   }
@@ skipping 1878 matching lines @@
     for (Element element in compiler.enqueuer.codegen.newlyEnqueuedElements) {
       if (element.isInstanceMember) {
         cachedClassBuilders.remove(element.enclosingClass);
 
         nativeEmitter.cachedBuilders.remove(element.enclosingClass);
 
       }
     }
   }
 }