Support idle time in CPU profiler

src/cpu-profiler.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 223 matching lines @@
   virtual void SetterCallbackEvent(Name* name, Address entry_point);
   virtual void SharedFunctionInfoMoveEvent(Address from, Address to);
 
   INLINE(bool is_profiling() const) { return is_profiling_; }
   bool* is_profiling_address() {
     return &is_profiling_;
   }
 
   ProfileGenerator* generator() const { return generator_; }
   ProfilerEventsProcessor* processor() const { return processor_; }
+  Isolate* isolate() const { return isolate_; }
 
  private:
   void StartProcessorIfNotStarted();
   void StopProcessorIfLastProfile(const char* title);
   void StopProcessor();
   void ResetProfiles();
   void LogBuiltins();
 
   Isolate* isolate_;
   CpuProfilesCollection* profiles_;
   unsigned next_profile_uid_;
   ProfileGenerator* generator_;
   ProfilerEventsProcessor* processor_;
   int saved_logging_nesting_;
   bool need_to_stop_sampler_;
   bool is_profiling_;
 
- private:
   DISALLOW_COPY_AND_ASSIGN(CpuProfiler);
 };
 
 } }  // namespace v8::internal
 
 
 #endif  // V8_CPU_PROFILER_H_