Move scanner into pkg/front_end/lib/src/scanner.

pkg/analyzer/test/src/dart/constant/evaluation_test.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.
 
 library analyzer.test.constant_test;
 
 import 'package:analyzer/context/declared_variables.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
@@ skipping 1178 matching lines @@
     expect(field.type.name, "int");
     expect(field.toIntValue(), expectedValue);
   }
 
   void _assertNullField(Map<String, DartObjectImpl> fields, String fieldName) {
     DartObjectImpl field = fields[fieldName];
     expect(field.isNull, isTrue);
   }
 
   void _assertProperDependencies(String sourceText,
-      [List<ErrorCode> expectedErrorCodes = ErrorCode.EMPTY_LIST]) {
+      [List<ErrorCode> expectedErrorCodes = const <ErrorCode>[]]) {
     Source source = addSource(sourceText);
     LibraryElement element = resolve2(source);
     CompilationUnit unit =
         analysisContext.resolveCompilationUnit(source, element);
     expect(unit, isNotNull);
     ConstantValueComputer computer = _makeConstantValueComputer();
     computer.add(unit);
     computer.computeValues();
     assertErrors(source, expectedErrorCodes);
   }
@@ skipping 394 matching lines @@
   }
 }
 
 @reflectiveTest
 class StrongConstantValueComputerTest extends ConstantValueComputerTest {
   void setUp() {
     super.setUp();
     resetWithOptions(new AnalysisOptionsImpl()..strongMode = true);
   }
 }