[nci] Check Isolate::concurrent_recompilation_enabled

... instead of FLAG_concurrent_recompilation. The
optimizing_compile_dispatcher may be nullptr despite the flag being
set.

Bug: v8:8888,chromium:1145988
Change-Id: Ia3a6b1a95dde2b8cdd43dd2beebf04c66f145f78
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2531781
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71116}

src/runtime/runtime-compiler.cc

@@ -311,7 +311,7 @@ RUNTIME_FUNCTION(Runtime_CompileForOnStackReplacement) {
 
     // Possibly compile for NCI caching.
     if (!MaybeSpawnNativeContextIndependentCompilationJob(
-            function, FLAG_concurrent_recompilation
+            function, isolate->concurrent_recompilation_enabled()
                           ? ConcurrencyMode::kConcurrent
                           : ConcurrencyMode::kNotConcurrent)) {
       return Object();

test/mjsunit/regress/regress-1145988.js

+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+__f_1();
+function __f_1() {
+  for (var __v_3 = 0; __v_3 < 100000; __v_3++) {
+  }
+}
+__f_1();