Finish strong mode cleaning of dart2js.

pkg/compiler/lib/src/js_emitter/full_emitter/class_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.
 
 library dart2js.js_emitter.full_emitter.class_emitter;
 
 import '../../common.dart';
 import '../../common/names.dart' show Names;
 import '../../common_elements.dart';
 import '../../elements/resolution_types.dart' show ResolutionDartType;
@@ skipping 107 matching lines @@
         return false;
       } else {
         fields = container.fields;
       }
     } else {
       assert(container is Library);
       assert(emitStatics);
       fields = container.staticFieldsForReflection;
     }
 
-    var fieldMetadata = [];
+    var fieldMetadata = <jsAst.Expression>[];
     bool hasMetadata = false;
     bool fieldsAdded = false;
 
     for (Field field in fields) {
       FieldEntity fieldElement = field.element;
       jsAst.Name name = field.name;
       jsAst.Name accessorName = field.accessorName;
       bool needsGetter = field.needsGetter;
       bool needsSetter = field.needsUncheckedSetter;
 
       // Ignore needsCheckedSetter - that is handled below.
       bool needsAccessor = (needsGetter || needsSetter);
       // We need to output the fields for non-native classes so we can auto-
       // generate the constructor.  For native classes there are no
       // constructors, so we don't need the fields unless we are generating
       // accessors at runtime.
       bool needsFieldsForConstructor = !emitStatics && !classIsNative;
       if (needsFieldsForConstructor || needsAccessor) {
-        var metadata =
+        dynamic metadata =
             task.metadataCollector.buildFieldMetadataFunction(fieldElement);
         if (metadata != null) {
           hasMetadata = true;
         } else {
           metadata = new jsAst.LiteralNull();
         }
         fieldMetadata.add(metadata);
         recordMangledField(fieldElement, accessorName,
             namer.privateName(fieldElement.memberName));
         List<jsAst.Literal> fieldNameParts = <jsAst.Literal>[];
@@ skipping 296 matching lines @@
     String reflectionName = emitter.getReflectionSelectorName(selector, name);
     if (reflectionName != null) {
       var reflectable = js(
           backend.mirrorsData.isMemberAccessibleByReflection(member)
               ? '1'
               : '0');
       builder.addPropertyByName('+$reflectionName', reflectable);
     }
   }
 }