Remove the Kernel setup_builtin_library transformation

pkg/kernel/lib/target/vm.dart

Index: pkg/kernel/lib/target/vm.dart
diff --git a/pkg/kernel/lib/target/vm.dart b/pkg/kernel/lib/target/vm.dart
index a043e3cb0dc36aabe1d048c38e9d7923fbba537a..003a21125e0aa5351b3fe3939f6440e2b165cdf2 100644
--- a/pkg/kernel/lib/target/vm.dart
+++ b/pkg/kernel/lib/target/vm.dart
@@ -12,7 +12,6 @@ import '../transformations/insert_covariance_checks.dart';
 import '../transformations/insert_type_checks.dart';
 import '../transformations/mixin_full_resolution.dart' as mix;
 import '../transformations/sanitize_for_vm.dart';
-import '../transformations/setup_builtin_library.dart' as setup_builtin_library;
 import '../transformations/treeshaker.dart';
 import 'targets.dart';
 
@@ -79,9 +78,6 @@ class VmTarget extends Target {
 
     cont.transformProgram(program);
 
-    // Repair `_getMainClosure()` function in dart:_builtin.
-    setup_builtin_library.transformProgram(program);
-
     if (strongMode) {
       performErasure(program);
     }