Move scanner out of generated and clean up imports

pkg/analyzer/test/generated/constant_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/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/resolver.dart';
-import 'package:analyzer/src/generated/scanner.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/generated/testing/ast_factory.dart';
 import 'package:analyzer/src/generated/testing/element_factory.dart';
 import 'package:analyzer/src/generated/testing/test_type_provider.dart';
 import 'package:analyzer/src/generated/utilities_collection.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:path/path.dart';
 import 'package:unittest/unittest.dart';
 
 import '../reflective_tests.dart';
 import '../utils.dart';
 import 'engine_test.dart';
 import 'resolver_test.dart';
 import 'test_support.dart';
 
-const int LONG_MAX_VALUE = 0x7fffffffffffffff;
-
 main() {
   initializeTestEnvironment();
   runReflectiveTests(ConstantEvaluatorTest);
   runReflectiveTests(ConstantFinderTest);
   runReflectiveTests(ConstantValueComputerTest);
   runReflectiveTests(ConstantVisitorTest);
   runReflectiveTests(DartObjectImplTest);
   runReflectiveTests(DeclaredVariablesTest);
   runReflectiveTests(ReferenceFinderTest);
 }
 
+const int LONG_MAX_VALUE = 0x7fffffffffffffff;
+
 /**
  * Implementation of [ConstantEvaluationValidator] used during unit tests;
  * verifies that any nodes referenced during constant evaluation are present in
  * the dependency graph.
  */
 class ConstantEvaluationValidator_ForTest
     implements ConstantEvaluationValidator {
   final InternalAnalysisContext context;
   ConstantValueComputer computer;
   ConstantEvaluationTarget _nodeBeingEvaluated;
@@ skipping 4476 matching lines @@
 
   void _visitNode(AstNode node) {
     node.accept(_createReferenceFinder(_head));
   }
 }
 
 class _TestAnalysisContext extends TestAnalysisContext {
   @override
   InternalAnalysisContext getContextFor(Source source) => this;
 }