Remove unnecessary casts.

Author: DanielRosenwasser

src/compiler/checker.ts

@@ -27699,7 +27699,7 @@ namespace ts {
                 error(expr, Diagnostics.The_operand_of_a_delete_operator_must_be_a_property_reference);
                 return booleanType;
             }
-            if (expr.kind === SyntaxKind.PropertyAccessExpression && isPrivateIdentifier((expr as PropertyAccessExpression).name)) {
+            if (expr.kind === SyntaxKind.PropertyAccessExpression && isPrivateIdentifier(expr.name)) {
                 error(expr, Diagnostics.The_operand_of_a_delete_operator_cannot_be_a_private_identifier);
             }
             const links = getNodeLinks(expr);

src/compiler/utilities.ts

@@ -4029,11 +4029,11 @@ namespace ts {
                         }
 
                         if (member.kind === SyntaxKind.GetAccessor && !getAccessor) {
-                            getAccessor = <GetAccessorDeclaration>member;
+                            getAccessor = member;
                         }
 
                         if (member.kind === SyntaxKind.SetAccessor && !setAccessor) {
-                            setAccessor = <SetAccessorDeclaration>member;
+                            setAccessor = member;
                         }
                     }
                 }