Issue 26821. Don't add 'void' return type for setters when lint 'avoid_return_types_on_setters' is …

pkg/analysis_server/lib/src/services/correction/fix_internal.dart

Index: pkg/analysis_server/lib/src/services/correction/fix_internal.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index 117884d2ca5bd8b9605c3a21b0b1c99559675891..763642ac103a87a4eef13fb578d5a8a4ce149bf7 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -1349,7 +1349,10 @@ class FixProcessor {
       sb.append(prefix);
     }
     // return type
-    _appendType(sb, element.type.returnType);
+    if (!isSetter) {
+      _appendType(sb, element.type.returnType);
+    }
+    // keyword
     if (isGetter) {
       sb.append('get ');
     } else if (isSetter) {