Use mutex in PostponeInterruptScope.

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1473 matching lines @@
 };
 
 
 // Support for temporarily postponing interrupts. When the outermost
 // postpone scope is left the interrupts will be re-enabled and any
 // interrupts that occurred while in the scope will be taken into
 // account.
 class PostponeInterruptsScope BASE_EMBEDDED {
  public:
   explicit PostponeInterruptsScope(Isolate* isolate)
-      : stack_guard_(isolate->stack_guard()) {
+      : stack_guard_(isolate->stack_guard()), isolate_(isolate) {
+    ExecutionAccess access(isolate_);
     stack_guard_->thread_local_.postpone_interrupts_nesting_++;
     stack_guard_->DisableInterrupts();
   }
 
   ~PostponeInterruptsScope() {
+    ExecutionAccess access(isolate_);
     if (--stack_guard_->thread_local_.postpone_interrupts_nesting_ == 0) {
       stack_guard_->EnableInterrupts();
     }
   }
  private:
   StackGuard* stack_guard_;
+  Isolate* isolate_;
 };
 
 
 // Tells whether the native context is marked with out of memory.
 inline bool Context::has_out_of_memory() {
   return native_context()->out_of_memory()->IsTrue();
 }
 
 
 // Mark the native context with out of memory.
@@ skipping 65 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_