Fix dart2js/analyze_unused_dart2js_test.

pkg/compiler/lib/src/ssa/builder_kernel.dart

 // Copyright (c) 2016, 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.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/names.dart';
 import '../common/tasks.dart' show CompilerTask;
@@ skipping 107 matching lines @@
       buildConstructor(target);
     }
     assert(graph.isValid());
     return graph;
   }
 
   void buildField(ir.Field field) {
     openFunction();
     if (field.initializer != null) {
       field.initializer.accept(this);
+      HInstruction fieldValue = pop();
+      HInstruction checkInstruction = typeBuilder.potentiallyCheckOrTrustType(
+          fieldValue, astAdapter.getDartType(field.type));
+      stack.add(checkInstruction);
     } else {
       stack.add(graph.addConstantNull(compiler));
     }
     HInstruction value = pop();
     closeAndGotoExit(new HReturn(value, null));
     closeFunction();
   }
 
   /// Pops the most recent instruction from the stack and 'boolifies' it.
   ///
@@ skipping 781 matching lines @@
     _visitLocalSetter(variableSet.variable, value);
   }
 
   @override
   void visitVariableDeclaration(ir.VariableDeclaration declaration) {
     Local local = astAdapter.getLocal(declaration);
     if (declaration.initializer == null) {
       HInstruction initialValue = graph.addConstantNull(compiler);
       localsHandler.updateLocal(local, initialValue);
     } else {
-      // TODO(het): handle case where the variable is top-level or static
       declaration.initializer.accept(this);
       HInstruction initialValue = pop();
 
       _visitLocalSetter(declaration, initialValue);
 
       // Ignore value
       pop();
     }
   }
 
   void _visitLocalSetter(ir.VariableDeclaration variable, HInstruction value) {
-    // TODO(het): handle case where the variable is top-level or static
     LocalElement local = astAdapter.getElement(variable);
 
     // Give the value a name if it doesn't have one already.
     if (value.sourceElement == null) {
       value.sourceElement = local;
     }
 
     stack.add(value);
     localsHandler.updateLocal(
         local,
@@ skipping 171 matching lines @@
     push(new HNot(popBoolified(), backend.boolType));
   }
 
   @override
   void visitStringConcatenation(ir.StringConcatenation stringConcat) {
     KernelStringBuilder stringBuilder = new KernelStringBuilder(this);
     stringConcat.accept(stringBuilder);
     stack.add(stringBuilder.result);
   }
 }