Elements. Migrate LabelScope.

Change-Id: I9891142ba33ea4d5bca1842ab8414dd89b4142eb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/411442
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

pkg/analyzer/lib/src/dart/resolver/resolution_visitor.dart

@@ -1012,7 +1012,7 @@ class ResolutionVisitor extends RecursiveAstVisitor<void> {
           _labelScope,
           labelNameNode.name,
           unlabeled,
-          labelNameNode.staticElement as LabelElement,
+          labelNameNode.element as LabelElement2,
         );
       }
       unlabeled.accept(this);

pkg/analyzer/lib/src/dart/resolver/scope.dart

@@ -93,7 +93,7 @@ class LabelScope {
   final String _label;
 
   /// The element to which the label resolves.
-  final LabelElement element;
+  final LabelElement2 element;
 
   /// The AST node to which the label resolves.
   final AstNode node;

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

@@ -5296,7 +5296,7 @@ class ScopeResolverVisitor extends UnifyingAstVisitor<void> {
       for (var member in node.members) {
         for (var label in member.labels) {
           var labelName = label.label;
-          var labelElement = labelName.staticElement as LabelElement;
+          var labelElement = labelName.element as LabelElement2;
           _labelScope =
               LabelScope(_labelScope, labelName.name, member, labelElement);
         }
@@ -5366,7 +5366,7 @@ class ScopeResolverVisitor extends UnifyingAstVisitor<void> {
     for (var label in labels) {
       var labelNameNode = label.label;
       var labelName = labelNameNode.name;
-      var labelElement = labelNameNode.staticElement as LabelElement;
+      var labelElement = labelNameNode.element as LabelElement2;
       _labelScope = LabelScope(_labelScope, labelName, node, labelElement);
     }
     return outerScope;
@@ -5409,9 +5409,9 @@ class ScopeResolverVisitor extends UnifyingAstVisitor<void> {
         return null;
       }
       // The target has been found.
-      labelNode.staticElement = definingScope.element;
-      ExecutableElement? labelContainer =
-          definingScope.element.thisOrAncestorOfType();
+      labelNode.element = definingScope.element;
+      var labelContainer =
+          definingScope.element.firstFragment.enclosingFragment;
       if (_enclosingClosure != null &&
           !identical(labelContainer, _enclosingClosure)) {
         errorReporter.atNode(