All strong mode cleaning of dart2js.

pkg/compiler/lib/src/resolution/signatures.dart

Index: pkg/compiler/lib/src/resolution/signatures.dart
diff --git a/pkg/compiler/lib/src/resolution/signatures.dart b/pkg/compiler/lib/src/resolution/signatures.dart
index 33dbfd8a1a312c5471201ba18f4c627f1625f993..ddc35286d569f93a52b8b1c6be0e8646b99958ba 100644
--- a/pkg/compiler/lib/src/resolution/signatures.dart
+++ b/pkg/compiler/lib/src/resolution/signatures.dart
@@ -35,7 +35,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
   final Scope scope;
   final MessageKind defaultValuesError;
   final bool createRealParameters;
-  List<Element> optionalParameters = const <Element>[];
+  List<FormalElement> optionalParameters = const <FormalElement>[];
   int optionalParameterCount = 0;
   bool isOptionalParameter = false;
   bool optionalParametersAreNamed = false;
@@ -65,7 +65,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
     }
     optionalParametersAreNamed = (identical(value, '{'));
     isOptionalParameter = true;
-    LinkBuilder<Element> elements = analyzeNodes(node.nodes);
+    LinkBuilder<FormalElement> elements = analyzeNodes(node.nodes);
     optionalParameterCount = elements.length;
     optionalParameters = elements.toList();
   }
@@ -252,7 +252,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
   }
 
   /// A [SendSet] node is an optional parameter with a default value.
-  Element visitSendSet(SendSet node) {
+  FormalElementX visitSendSet(SendSet node) {
     FormalElementX element;
     if (node.receiver != null) {
       element = createFieldParameter(node, node.arguments.first);
@@ -267,7 +267,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
     return element;
   }
 
-  Element visitFunctionExpression(FunctionExpression node) {
+  FormalElementX visitFunctionExpression(FunctionExpression node) {
     // This is a function typed parameter.
     Modifiers modifiers = currentDefinitions.modifiers;
     if (modifiers.isFinal) {
@@ -282,8 +282,8 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
     return createParameter(node.name, null);
   }
 
-  LinkBuilder<Element> analyzeNodes(Link<Node> link) {
-    LinkBuilder<Element> elements = new LinkBuilder<Element>();
+  LinkBuilder<FormalElement> analyzeNodes(Link<Node> link) {
+    LinkBuilder<FormalElement> elements = new LinkBuilder<FormalElement>();
     for (; !link.isEmpty; link = link.tail) {
       Element element = link.head.accept(this);
       if (element != null) {
@@ -356,7 +356,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
         resolution, element, scope, registry,
         defaultValuesError: defaultValuesError,
         createRealParameters: createRealParameters);
-    List<Element> parameters = const <Element>[];
+    List<FormalElement> parameters = const <FormalElement>[];
     int requiredParameterCount = 0;
     if (formalParameters == null) {
       if (!element.isGetter) {
@@ -380,7 +380,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
               formalParameters, MessageKind.EXTRA_FORMALS);
         }
       }
-      LinkBuilder<Element> parametersBuilder =
+      LinkBuilder<FormalElement> parametersBuilder =
           visitor.analyzeNodes(formalParameters.nodes);
       requiredParameterCount = parametersBuilder.length;
       parameters = parametersBuilder.toList();
@@ -438,7 +438,7 @@ class SignatureResolver extends MappingVisitor<FormalElementX> {
         const <ResolutionDartType>[];
     List<String> namedParameters = const <String>[];
     List<ResolutionDartType> namedParameterTypes = const <ResolutionDartType>[];
-    List<Element> orderedOptionalParameters =
+    List<FormalElement> orderedOptionalParameters =
         visitor.optionalParameters.toList();
     if (visitor.optionalParametersAreNamed) {
       // TODO(karlklose); replace when [visitor.optionalParameters] is a [List].