Elements. Remove MethodElementOrMember.

Change-Id: I062e1a55867ba541290ed948081cf4ea26dab2cf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/437320
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

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

@@ -7753,21 +7753,8 @@ class MethodElementImpl extends ExecutableElementImpl
   }
 }
 
-/// Common base class for all analyzer-internal classes that implement
-/// `MethodElement`.
-abstract class MethodElementOrMember implements ExecutableElementOrMember {
-  @override
-  TypeImpl get returnType;
-
-  @override
-  FunctionTypeImpl get type;
-
-  @override
-  List<TypeParameterFragmentImpl> get typeParameters;
-}
-
 class MethodFragmentImpl extends ExecutableFragmentImpl
-    implements MethodElementOrMember, MethodFragment {
+    implements MethodFragment {
   @override
   late final MethodElementImpl element;
 

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

@@ -2321,14 +2321,14 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
       String name = accessor.displayName;
 
       // find inherited method or property accessor
-      var inherited =
-          _inheritanceManager
-              .getInherited(enclosingClass, Name(libraryUri, name))
-              ?.asElement;
-      inherited ??=
-          _inheritanceManager
-              .getInherited(enclosingClass, Name(libraryUri, '$name='))
-              ?.asElement;
+      var inherited = _inheritanceManager.getInherited(
+        enclosingClass,
+        Name(libraryUri, name),
+      );
+      inherited ??= _inheritanceManager.getInherited(
+        enclosingClass,
+        Name(libraryUri, '$name='),
+      );
 
       if (accessor.isStatic && inherited != null) {
         diagnosticReporter.atElement2(
@@ -2337,11 +2337,11 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
           arguments: [
             enclosingClass.displayName,
             name,
-            inherited.asElement2.enclosingElement!.displayName,
+            inherited.enclosingElement!.displayName,
           ],
         );
         conflictingDeclaredNames.add(name);
-      } else if (inherited is MethodElementOrMember) {
+      } else if (inherited is MethodElement2OrMember) {
         // Extension type accessors preclude inherited accessors/methods.
         if (enclosingClass is ExtensionTypeElementImpl) {
           continue;
@@ -2352,7 +2352,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
           arguments: [
             enclosingClass.displayName,
             name,
-            inherited.asElement2.enclosingElement!.displayName,
+            inherited.enclosingElement!.displayName,
           ],
         );
         conflictingDeclaredNames.add(name);

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

@@ -404,16 +404,6 @@ extension MethodElementImplExtension on MethodFragmentImpl {
   }
 }
 
-extension MethodElementOrMemberExtension on MethodElementOrMember {
-  MethodElement2OrMember get asElement2 {
-    return switch (this) {
-      MethodFragmentImpl(:var element) => element,
-      MethodMember member => member,
-      _ => throw UnsupportedError('Unsupported type: $runtimeType'),
-    };
-  }
-}
-
 extension MixinElementImplExtension on MixinFragmentImpl {
   MixinElementImpl get asElement2 {
     return element;