Fully delete _NonTopLevelVariableOrParameter

Change-Id: I9bd842390692ead2ddf2ca02ce615d4148a2b8b1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/440800
Reviewed-by: Konstantin Shcheglov <[email protected]>
Commit-Queue: Paul Berry <[email protected]>
Reviewed-by: Paul Berry <[email protected]>

Author: fshcheglov

pkg/analyzer/lib/src/dart/element/element.dart

@@ -2960,11 +2960,9 @@ class FormalParameterElementImpl extends PromotableElementImpl
         FragmentedAnnotatableElementMixin<FormalParameterFragmentImpl>,
         FragmentedElementMixin<FormalParameterFragmentImpl>,
         FormalParameterElementMixin,
-        _HasSinceSdkVersionMixin,
-        _NonTopLevelVariableOrParameter {
+        _HasSinceSdkVersionMixin {
   @override
   Reference? reference;
-
   final FormalParameterFragmentImpl wrappedElement;
 
   @override
@@ -3002,6 +3000,15 @@ class FormalParameterElementImpl extends PromotableElementImpl
     return constantInitializer2?.expression.toSource();
   }
 
+  @override
+  Element? get enclosingElement {
+    return wrappedElement.enclosingElement?.element;
+  }
+
+  @Deprecated('Use enclosingElement instead')
+  @override
+  Element? get enclosingElement2 => enclosingElement;
+
   @override
   FormalParameterFragmentImpl get firstFragment => wrappedElement;
 
@@ -3127,9 +3134,6 @@ class FormalParameterElementImpl extends PromotableElementImpl
   @override
   TypeImpl get typeShared => type;
 
-  @override
-  FragmentImpl? get _enclosingFunction => wrappedElement.enclosingElement;
-
   @override
   T? accept<T>(ElementVisitor2<T> visitor) {
     return visitor.visitFormalParameterElement(this);
@@ -6970,7 +6974,6 @@ class LocalFunctionFragmentImpl extends FunctionFragmentImpl
 }
 
 class LocalVariableElementImpl extends PromotableElementImpl
-    with _NonTopLevelVariableOrParameter
     implements LocalVariableElement {
   final LocalVariableFragmentImpl _wrappedElement;
 
@@ -6985,6 +6988,15 @@ class LocalVariableElementImpl extends PromotableElementImpl
   @override
   String? get documentationComment => null;
 
+  @override
+  Element? get enclosingElement {
+    return _wrappedElement.enclosingElement.element;
+  }
+
+  @Deprecated('Use enclosingElement instead')
+  @override
+  Element? get enclosingElement2 => enclosingElement;
+
   @override
   LocalVariableFragmentImpl get firstFragment => _wrappedElement;
 
@@ -7035,9 +7047,6 @@ class LocalVariableElementImpl extends PromotableElementImpl
   @override
   String? get name3 => name;
 
-  @override
-  FragmentImpl? get _enclosingFunction => _wrappedElement.enclosingElement;
-
   @override
   T? accept<T>(ElementVisitor2<T> visitor) {
     return visitor.visitLocalVariableElement(this);
@@ -9932,8 +9941,7 @@ abstract class TypeDefiningElementImpl extends ElementImpl
 class TypeParameterElementImpl extends TypeDefiningElementImpl
     with
         FragmentedAnnotatableElementMixin<TypeParameterFragmentImpl>,
-        FragmentedElementMixin<TypeParameterFragmentImpl>,
-        _NonTopLevelVariableOrParameter
+        FragmentedElementMixin<TypeParameterFragmentImpl>
     implements TypeParameterElement, SharedTypeParameter {
   @override
   final TypeParameterFragmentImpl firstFragment;
@@ -9972,6 +9980,15 @@ class TypeParameterElementImpl extends TypeDefiningElementImpl
   /// fall-back type value in type inference.
   TypeImpl? get defaultType => firstFragment.defaultType;
 
+  @override
+  Element? get enclosingElement {
+    return firstFragment.enclosingElement?.element;
+  }
+
+  @Deprecated('Use enclosingElement instead')
+  @override
+  Element? get enclosingElement2 => enclosingElement;
+
   @override
   List<TypeParameterFragmentImpl> get fragments {
     return [
@@ -10006,9 +10023,6 @@ class TypeParameterElementImpl extends TypeDefiningElementImpl
     firstFragment.variance = value;
   }
 
-  @override
-  FragmentImpl? get _enclosingFunction => firstFragment.enclosingElement;
-
   @override
   T? accept<T>(ElementVisitor2<T> visitor) {
     return visitor.visitTypeParameterElement(this);
@@ -10550,20 +10564,6 @@ mixin _HasSinceSdkVersionMixin on ElementImpl, Annotatable
   }
 }
 
-mixin _NonTopLevelVariableOrParameter on Element {
-  @override
-  Element? get enclosingElement {
-    // TODO(dantup): Can we simplify this code and inline it into each class?
-    return _enclosingFunction?.element;
-  }
-
-  @Deprecated('Use enclosingElement instead')
-  @override
-  Element? get enclosingElement2 => enclosingElement;
-
-  FragmentImpl? get _enclosingFunction;
-}
-
 /// Instances of [List]s that are used as "not yet computed" values, they
 /// must be not `null`, and not identical to `const <T>[]`.
 class _Sentinel {