[sparkplug] Update DCHECK to work with fuzzers

There was a DCHECK to ensure tests don't miss enabling either bytecode
or baseline code flushing along with stress-flush-code. Fuzzers use
different combination of flags so there we should allow
stress-flush-code without bytecode / baseline code flushing.

Bug: chromium:1236614,v8:11947
Change-Id: I86190b6336015e37288cffffc05de2fa21f496ad
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3074462
Commit-Queue: Mythri Alle <mythria@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Auto-Submit: Mythri Alle <mythria@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76115}

src/heap/heap-inl.h

@@ -100,7 +100,10 @@ base::EnumSet<CodeFlushMode> Heap::GetCodeFlushMode(Isolate* isolate) {
   }
 
   if (FLAG_stress_flush_code) {
-    DCHECK(FLAG_flush_baseline_code || FLAG_flush_bytecode);
+    // This is to check tests accidentally don't miss out on adding either flush
+    // bytecode or flush code along with stress flush code. stress_flush_code
+    // doesn't do anything if either one of them isn't enabled.
+    DCHECK(FLAG_fuzzing || FLAG_flush_baseline_code || FLAG_flush_bytecode);
     code_flush_mode.Add(CodeFlushMode::kStressFlushCode);
   }