Move SimulatorHelper into V8 out of profiler clients.

src/profiler/tick-sample.h

Index: src/profiler/tick-sample.h
diff --git a/src/profiler/tick-sample.h b/src/profiler/tick-sample.h
index c7c42e63a28d10f6216d68179989247814e17d16..df6d0cb0797b6c200550da62371f51d1544c9235 100644
--- a/src/profiler/tick-sample.h
+++ b/src/profiler/tick-sample.h
@@ -15,21 +15,11 @@ namespace internal {
 class Isolate;
 
 struct TickSample : public v8::TickSample {
-  TickSample() : v8::TickSample() {}
   void Init(Isolate* isolate, const v8::RegisterState& state,
             RecordCEntryFrame record_c_entry_frame, bool update_stats);
   base::TimeTicks timestamp;
 };
 
-#if defined(USE_SIMULATOR)
-class SimulatorHelper {
- public:
-  // Returns true if register values were successfully retrieved
-  // from the simulator, otherwise returns false.
-  static bool FillRegisters(Isolate* isolate, v8::RegisterState* state);
-};
-#endif  // USE_SIMULATOR
-
 }  // namespace internal
 }  // namespace v8