Revert "[d8] quit() should not dispose the isolate"

This reverts commit 9981f2e5.

Reason for revert: This CL landed by accident, we decided back then to land a different CL.

Original change's description:
> [d8] quit() should not dispose the isolate
>
> R=​cbruni@chromium.org
>
> Bug: chromium:1338150
> Change-Id: I5e5f8ede942dd37112766812a3c84a356f0b6ca9
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714355
> Reviewed-by: Camillo Bruni <cbruni@chromium.org>
> Commit-Queue: Andreas Haas <ahaas@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81827}

Bug: chromium:1338150
Change-Id: Ib058d90a0c09e7cc65bdecee20580dd9e1f184d9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3773776
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Auto-Submit: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81838}

src/d8/d8.cc

@@ -2769,7 +2769,18 @@ void Shell::QuitOnce(v8::FunctionCallbackInfo<v8::Value>* args) {
   int exit_code = (*args)[0]
                       ->Int32Value(args->GetIsolate()->GetCurrentContext())
                       .FromMaybe(0);
-  PrintCounters();
+  Isolate* isolate = args->GetIsolate();
+  isolate->Exit();
+
+  // As we exit the process anyway, we do not dispose the platform and other
+  // global data and manually unlock to quell DCHECKs. Other isolates might
+  // still be running, so disposing here can cause them to crash.
+  i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  if (i_isolate->thread_manager()->IsLockedByCurrentThread()) {
+    i_isolate->thread_manager()->Unlock();
+  }
+
+  OnExit(isolate, false);
   base::OS::ExitProcess(exit_code);
 }
 
@@ -3659,7 +3670,25 @@ void Shell::WriteLcovData(v8::Isolate* isolate, const char* file) {
   }
 }
 
-void Shell::PrintCounters() {
+void Shell::OnExit(v8::Isolate* isolate, bool dispose) {
+  isolate->Dispose();
+  if (shared_isolate) {
+    i::Isolate::Delete(reinterpret_cast<i::Isolate*>(shared_isolate));
+  }
+
+  // Simulate errors before disposing V8, as that resets flags (via
+  // FlagList::ResetAllFlags()), but error simulation reads the random seed.
+  if (options.simulate_errors && is_valid_fuzz_script()) {
+    // Simulate several errors detectable by fuzzers behind a flag if the
+    // minimum file size for fuzzing was executed.
+    FuzzerMonitor::SimulateErrors();
+  }
+
+  if (dispose) {
+    V8::Dispose();
+    V8::DisposePlatform();
+  }
+
   if (options.dump_counters || options.dump_counters_nvp) {
     base::SharedMutexGuard<base::kShared> mutex_guard(&counter_mutex_);
     std::vector<std::pair<std::string, Counter*>> counters(
@@ -3709,27 +3738,6 @@ void Shell::PrintCounters() {
                 << std::string(kValueBoxSize, '-') << "+\n";
     }
   }
-}
-
-void Shell::OnExit(v8::Isolate* isolate, bool dispose) {
-  isolate->Dispose();
-  if (shared_isolate) {
-    i::Isolate::Delete(reinterpret_cast<i::Isolate*>(shared_isolate));
-  }
-
-  // Simulate errors before disposing V8, as that resets flags (via
-  // FlagList::ResetAllFlags()), but error simulation reads the random seed.
-  if (options.simulate_errors && is_valid_fuzz_script()) {
-    // Simulate several errors detectable by fuzzers behind a flag if the
-    // minimum file size for fuzzing was executed.
-    FuzzerMonitor::SimulateErrors();
-  }
-
-  if (dispose) {
-    V8::Dispose();
-    V8::DisposePlatform();
-  }
-  PrintCounters();
 
   // Only delete the counters if we are done executing; after calling `quit`,
   // other isolates might still be running and accessing that memory. This is a

src/d8/d8.h

@@ -520,7 +520,6 @@ class Shell : public i::AllStatic {
   static int RunMain(Isolate* isolate, bool last_run);
   static int Main(int argc, char* argv[]);
   static void Exit(int exit_code);
-  static void PrintCounters();
   static void OnExit(Isolate* isolate, bool dispose);
   static void CollectGarbage(Isolate* isolate);
   static bool EmptyMessageQueues(Isolate* isolate);