Fix hints

pkg/analyzer/lib/src/generated/constant.dart

 // Copyright (c) 2014, 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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.constant;
 
 import 'dart:collection';
@@ skipping 415 matching lines @@
     _variableDeclarationMap = _constantFinder.variableMap;
     constructorDeclarationMap = _constantFinder.constructorMap;
     _constructorInvocations = _constantFinder.constructorInvocations;
     _annotations = _constantFinder.annotations;
     _variableDeclarationMap.values.forEach((VariableDeclaration declaration) {
       ReferenceFinder referenceFinder = new ReferenceFinder(declaration,
           referenceGraph, _variableDeclarationMap, constructorDeclarationMap);
       referenceGraph.addNode(declaration);
       declaration.initializer.accept(referenceFinder);
     });
-    constructorDeclarationMap.forEach(
-        (ConstructorElement element, ConstructorDeclaration declaration) {
+    constructorDeclarationMap.forEach((ConstructorElement element,
+        ConstructorDeclaration declaration) {
       ReferenceFinder referenceFinder = new ReferenceFinder(declaration,
           referenceGraph, _variableDeclarationMap, constructorDeclarationMap);
       referenceGraph.addNode(declaration);
       bool superInvocationFound = false;
       NodeList<ConstructorInitializer> initializers = declaration.initializers;
       for (ConstructorInitializer initializer in initializers) {
         if (initializer is SuperConstructorInvocation) {
           superInvocationFound = true;
         }
         initializer.accept(referenceFinder);
@@ skipping 407 matching lines @@
       if (errorTarget == null) {
         // No argument node that we can direct error messages to, because we
         // are handling an optional parameter that wasn't specified.  So just
         // direct error messages to the constructor call.
         errorTarget = node;
       }
       if (argumentValue == null && baseParameter is ParameterElementImpl) {
         // The parameter is an optional positional parameter for which no value
         // was provided, so use the default value.
         beforeGetParameterDefault(baseParameter);
-        EvaluationResultImpl evaluationResult =
-            (baseParameter as ParameterElementImpl).evaluationResult;
+        EvaluationResultImpl evaluationResult = baseParameter.evaluationResult;
         if (evaluationResult == null) {
           // No default was provided, so the default value is null.
           argumentValue = constantVisitor.null2;
         } else if (evaluationResult.value != null) {
           argumentValue = evaluationResult.value;
         }
       }
       if (argumentValue != null) {
         if (!_runtimeTypeMatch(argumentValue, parameter.type)) {
           errorReporter.reportErrorForNode(
@@ skipping 4050 matching lines @@
     return null;
   }
 
   @override
   Object visitSimpleIdentifier(SimpleIdentifier node) {
     Element element = node.staticElement;
     if (element is PropertyAccessorElement) {
       element = (element as PropertyAccessorElement).variable;
     }
     if (element is VariableElement) {
-      VariableElement variable = element as VariableElement;
-      if (variable.isConst) {
+      if (element.isConst) {
         VariableDeclaration variableDeclaration =
-            _variableDeclarationMap[variable];
+            _variableDeclarationMap[element];
         // The declaration will be null when the variable is not defined in the
         // compilation units that were used to produce the
         // variableDeclarationMap.  In such cases, the variable should already
         // have a value associated with it, but we don't bother to check because
         // there's nothing we can do about it at this point.
         if (variableDeclaration != null) {
           _referenceGraph.addEdge(_source, variableDeclaration);
         }
       }
     }
@@ skipping 234 matching lines @@
       return BoolState.from(_element == rightElement);
     } else if (rightOperand is DynamicState) {
       return BoolState.UNKNOWN_VALUE;
     }
     return BoolState.FALSE_STATE;
   }
 
   @override
   String toString() => _element == null ? "-unknown-" : _element.name;
 }