Add {CancelableTaskManager} to handle {Cancelable} concurrent tasks.

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include <queue>
 #include <set>
 
@@ skipping 1075 matching lines @@
 
   void set_array_buffer_allocator(v8::ArrayBuffer::Allocator* allocator) {
     array_buffer_allocator_ = allocator;
   }
   v8::ArrayBuffer::Allocator* array_buffer_allocator() const {
     return array_buffer_allocator_;
   }
 
   FutexWaitListNode* futex_wait_list_node() { return &futex_wait_list_node_; }
 
-  void RegisterCancelableTask(Cancelable* task);
-  void RemoveCancelableTask(Cancelable* task);
+  CancelableTaskManager* cancelable_task_manager() {
+    return cancelable_task_manager_;
+  }
 
   interpreter::Interpreter* interpreter() const { return interpreter_; }
 
  protected:
   explicit Isolate(bool enable_serializer);
 
  private:
   friend struct GlobalState;
   friend struct InitializeGlobalState;
   Handle<JSObject> SetUpSubregistry(Handle<JSObject> registry, Handle<Map> map,
@@ skipping 223 matching lines @@
 
   v8::Isolate::UseCounterCallback use_counter_callback_;
   BasicBlockProfiler* basic_block_profiler_;
 
   List<Object*> partial_snapshot_cache_;
 
   v8::ArrayBuffer::Allocator* array_buffer_allocator_;
 
   FutexWaitListNode futex_wait_list_node_;
 
-  std::set<Cancelable*> cancelable_tasks_;
+  CancelableTaskManager* cancelable_task_manager_;
 
   v8::Isolate::AbortOnUncaughtExceptionCallback
       abort_on_uncaught_exception_callback_;
 
   friend class ExecutionAccess;
   friend class HandleScopeImplementer;
   friend class OptimizingCompileDispatcher;
   friend class SweeperThread;
   friend class ThreadManager;
   friend class Simulator;
@@ skipping 213 matching lines @@
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ISOLATE_H_