Split Ticker into two samplers.

src/profiler/cpu-profiler.h

Index: src/profiler/cpu-profiler.h
diff --git a/src/profiler/cpu-profiler.h b/src/profiler/cpu-profiler.h
index d354aeb0469584ee27bdf94429461e262d51fd8e..f9c6c072f3631886578df4782136ff61e77a313f 100644
--- a/src/profiler/cpu-profiler.h
+++ b/src/profiler/cpu-profiler.h
@@ -133,8 +133,7 @@ class CodeEventsContainer {
 // methods called by event producers: VM and stack sampler threads.
 class ProfilerEventsProcessor : public base::Thread {
  public:
-  ProfilerEventsProcessor(ProfileGenerator* generator,
-                          sampler::Sampler* sampler,
+  ProfilerEventsProcessor(Isolate* isolate, ProfileGenerator* generator,
                           base::TimeDelta period);
   virtual ~ProfilerEventsProcessor();
 
@@ -160,6 +159,8 @@ class ProfilerEventsProcessor : public base::Thread {
   void* operator new(size_t size);
   void operator delete(void* ptr);
 
+  sampler::Sampler* sampler() { return sampler_; }
+
  private:
   // Called from events processing thread (Run() method.)
   bool ProcessCodeEvent();
@@ -209,10 +210,6 @@ class CpuProfiler : public CodeEventObserver {
 
   void CodeEventHandler(const CodeEventsContainer& evt_rec) override;
 
-  // Invoked from stack sampler (thread or signal handler.)
-  inline TickSample* StartTickSample();
-  inline void FinishTickSample();
-
   bool is_profiling() const { return is_profiling_; }
 
   ProfileGenerator* generator() const { return generator_.get(); }