Initial GetSample implementation.

src/cpu-profiler.h

Index: src/cpu-profiler.h
diff --git a/src/cpu-profiler.h b/src/cpu-profiler.h
index d666255b0af56539daa4e3c374cd255308a4ebe4..8ebc20cb3a2e22bcf59644bd0ba08ab81bf0fd3c 100644
--- a/src/cpu-profiler.h
+++ b/src/cpu-profiler.h
@@ -145,6 +145,8 @@ class ProfilerEventsProcessor : public base::Thread {
   inline TickSample* StartTickSample();
   inline void FinishTickSample();
 
+  Sampler* sampler() const { return sampler_; }
+
   // SamplingCircularQueue has stricter alignment requirements than a normal new
   // can fulfil, so we need to provide our own new/delete here.
   void* operator new(size_t size);