Avoid emitting addStubs and tearOffCode when not needed.

pkg/dart2js_incremental/lib/caching_compiler.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_incremental;
 
 /// Do not call this method directly. It will be made private.
 // TODO(ahe): Make this method private.
 Future<Compiler> reuseCompiler(
     {DiagnosticHandler diagnosticHandler,
@@ skipping 53 matching lines @@
         packageRoot,
         options,
         environment);
     JavaScriptBackend backend = compiler.backend;
 
     // Much like a scout, an incremental compiler is always prepared. For
     // mixins, classes, and lazy statics, at least.
     backend.emitter.oldEmitter
         ..needsClassSupport = true
         ..needsMixinSupport = true
-        ..needsLazyInitializer = true;
+        ..needsLazyInitializer = true
+        ..needsArrayInitializerSupport = true;
 
     Uri core = Uri.parse("dart:core");
     return compiler.libraryLoader.loadLibrary(core).then((_) {
       // Likewise, always be prepared for runtimeType support.
       // TODO(johnniwinther): Add global switch to force RTI.
       compiler.enabledRuntimeType = true;
       backend.registerRuntimeType(
           compiler.enqueuer.resolution, compiler.globalDependencies);
       return compiler;
     });
@@ skipping 118 matching lines @@
   final Map<String, String> output = new Map<String, String>();
 
   EventSink<String> call(String name, String extension) {
     return new StringEventSink((String data) {
       output['$name.$extension'] = data;
     });
   }
 
   String operator[] (String key) => output[key];
 }