Static warning fixes.

pkg/analyzer/lib/src/task/options.dart

 // Copyright (c) 2015, 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.src.task.options;
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/plugin/options.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 108 matching lines @@
 
 /// Validates `analyzer` error filter options.
 class ErrorFilterOptionValidator extends OptionsValidator {
   /// Pretty list of legal includes.
   static final String legalIncludes = StringUtilities.printListOfQuotedNames(
       new List.from(AnalyzerOptions.ignoreSynonyms)
         ..addAll(AnalyzerOptions.includeSynonyms));
 
   @override
   void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
-    YamlNode analyzer = options[AnalyzerOptions.analyzer];
+    var analyzer = options[AnalyzerOptions.analyzer];
     if (analyzer is! YamlMap) {
       return;
     }
 
-    YamlNode filters = analyzer[AnalyzerOptions.errors];
+    var filters = analyzer[AnalyzerOptions.errors];
     if (filters is YamlMap) {
       String value;
       filters.nodes.forEach((k, v) {
         if (k is YamlScalar) {
           value = toUpperCase(k.value);
           if (!ErrorCode.values.any((ErrorCode code) => code.name == value)) {
             reporter.reportErrorForSpan(
                 AnalysisOptionsWarningCode.UNRECOGNIZED_ERROR_CODE,
                 k.span,
                 [k.value?.toString()]);
@@ skipping 81 matching lines @@
       new GenerateOptionsErrorsTask(context, target);
 }
 
 /// Validates `analyzer` language configuration options.
 class LanguageOptionValidator extends OptionsValidator {
   ErrorBuilder builder = new ErrorBuilder(AnalyzerOptions.languageOptions);
   ErrorBuilder trueOrFalseBuilder = new TrueOrFalseValueErrorBuilder();
 
   @override
   void validate(ErrorReporter reporter, Map<String, YamlNode> options) {
-    YamlNode analyzer = options[AnalyzerOptions.analyzer];
+    var analyzer = options[AnalyzerOptions.analyzer];
     if (analyzer is! YamlMap) {
       return;
     }
 
-    YamlNode language = analyzer[AnalyzerOptions.language];
+    var language = analyzer[AnalyzerOptions.language];
     if (language is YamlMap) {
       language.nodes.forEach((k, v) {
         String key, value;
         bool validKey = false;
         if (k is YamlScalar) {
           key = k.value?.toString();
           if (!AnalyzerOptions.languageOptions.contains(key)) {
             builder.reportError(reporter, AnalyzerOptions.language, k);
           } else {
             // If we have a valid key, go on and check the value.
@@ skipping 164 matching lines @@
   void setStrongMode(AnalysisContext context, Object strongMode) {
     bool strong = strongMode is bool ? strongMode : false;
     if (context.analysisOptions.strongMode != strong) {
       AnalysisOptionsImpl options =
           new AnalysisOptionsImpl.from(context.analysisOptions);
       options.strongMode = strong;
       context.analysisOptions = options;
     }
   }
 }