d8 workers: make sure Shell::Quit is only called once

When running with isolates, Quit can be called simultaneously by two threads.
If this happens, then both threads try to clean up the Workers, which could
crash.

BUG=v8:4279
R=jarin@chromium.org
R=machenbach@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/1230403003

Cr-Commit-Position: refs/heads/master@{#29654}

src/d8.cc

@@ -216,6 +216,7 @@ Persistent<Context> Shell::evaluation_context_;
 ArrayBuffer::Allocator* Shell::array_buffer_allocator;
 ShellOptions Shell::options;
 const char* Shell::kPrompt = "d8> ";
+base::OnceType Shell::quit_once_ = V8_ONCE_INIT;
 
 #ifndef V8_SHARED
 bool CounterMap::Match(void* key1, void* key2) {
@@ -809,16 +810,22 @@ void Shell::WorkerTerminate(const v8::FunctionCallbackInfo<v8::Value>& args) {
 #endif  // !V8_SHARED
 
 
-void Shell::Quit(const v8::FunctionCallbackInfo<v8::Value>& args) {
-  int exit_code = args[0]->Int32Value();
+void Shell::QuitOnce(v8::FunctionCallbackInfo<v8::Value>* args) {
+  int exit_code = (*args)[0]->Int32Value();
 #ifndef V8_SHARED
   CleanupWorkers();
 #endif  // !V8_SHARED
-  OnExit(args.GetIsolate());
+  OnExit(args->GetIsolate());
   exit(exit_code);
 }
 
 
+void Shell::Quit(const v8::FunctionCallbackInfo<v8::Value>& args) {
+  base::CallOnce(&quit_once_, &QuitOnce,
+                 const_cast<v8::FunctionCallbackInfo<v8::Value>*>(&args));
+}
+
+
 void Shell::Version(const v8::FunctionCallbackInfo<v8::Value>& args) {
   args.GetReturnValue().Set(
       String::NewFromUtf8(args.GetIsolate(), V8::GetVersion()));

src/d8.h

@@ -15,6 +15,9 @@
 #include "src/base/compiler-specific.h"
 #endif  // !V8_SHARED
 
+#include "src/base/once.h"
+
+
 namespace v8 {
 
 
@@ -411,6 +414,7 @@ class Shell : public i::AllStatic {
 
   static void Print(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Write(const v8::FunctionCallbackInfo<v8::Value>& args);
+  static void QuitOnce(v8::FunctionCallbackInfo<v8::Value>* args);
   static void Quit(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Version(const v8::FunctionCallbackInfo<v8::Value>& args);
   static void Read(const v8::FunctionCallbackInfo<v8::Value>& args);
@@ -468,6 +472,7 @@ class Shell : public i::AllStatic {
 
  private:
   static Persistent<Context> evaluation_context_;
+  static base::OnceType quit_once_;
 #ifndef V8_SHARED
   static Persistent<Context> utility_context_;
   static CounterMap* counter_map_;

test/mjsunit/mjsunit.status

@@ -248,9 +248,6 @@
   # BUG(chromium:508074). Remove this once the issue is fixed.
   'harmony/arrow-rest-params': [PASS, NO_VARIANTS],
   'harmony/rest-params': [PASS, ['no_snap == True', NO_VARIANTS]],
-
-  # BUG(v8:4279).
-  'regress/regress-4279': [PASS, ['isolates', SKIP]],
 }],  # ALWAYS
 
 ['novfp3 == True', {