[d8] Make --stress-delay-tasks a d8-specific flag

The flag is only available in d8 and should therefore not be in
flag-definitions.h.

R=clemensh@chromium.org

Bug: v8:8238
Change-Id: Idd69914cea03e736cf3b156b5961d583a7b5352c
Reviewed-on: https://chromium-review.googlesource.com/c/1349244
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57829}

src/d8.cc

@@ -2895,6 +2895,10 @@ bool Shell::SetOptions(int argc, char* argv[]) {
     } else if (strncmp(argv[i], "--thread-pool-size=", 19) == 0) {
       options.thread_pool_size = atoi(argv[i] + 19);
       argv[i] = nullptr;
+    } else if (strcmp(argv[i], "--stress-delay-tasks") == 0) {
+      // Delay execution of tasks by 0-100ms randomly (based on --random-seed).
+      options.stress_delay_tasks = true;
+      argv[i] = nullptr;
     }
   }
 
@@ -3355,7 +3359,7 @@ int Shell::Main(int argc, char* argv[]) {
   if (i::FLAG_verify_predictable) {
     g_platform = MakePredictablePlatform(std::move(g_platform));
   }
-  if (i::FLAG_stress_delay_tasks) {
+  if (options.stress_delay_tasks) {
     int64_t random_seed = i::FLAG_fuzzer_random_seed;
     if (!random_seed) random_seed = i::FLAG_random_seed;
     // If random_seed is still 0 here, the {DelayedTasksPlatform} will choose a

src/d8.h

@@ -386,6 +386,7 @@ class ShellOptions {
   bool enable_os_system = false;
   bool quiet_load = false;
   int thread_pool_size = 0;
+  bool stress_delay_tasks = false;
   std::vector<const char*> arguments;
   bool include_arguments = true;
 };

src/flag-definitions.h

@@ -324,11 +324,6 @@ DEFINE_BOOL(enable_one_shot_optimization, true,
 DEFINE_BOOL(unbox_double_arrays, true, "automatically unbox arrays of doubles")
 DEFINE_BOOL_READONLY(string_slices, true, "use string slices")
 
-// Flag to stress different interleavings of tasks.
-DEFINE_BOOL(
-    stress_delay_tasks, false,
-    "delay execution of tasks by 0-100ms randomly (based on --random-seed)")
-
 // Flags for Ignition for no-snapshot builds.
 #undef FLAG
 #ifndef V8_USE_SNAPSHOT