Initial implementation of GetStackSample sampling profiler API.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 2096efd4afdb8c8b7b6994b0614b09e1b290d64f..488b517ac23b5802b84523a2a54d91994bcf245a 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -40,6 +40,7 @@
 #include "src/prototype.h"
 #include "src/runtime.h"
 #include "src/runtime-profiler.h"
+#include "src/sampler.h"
 #include "src/scanner-character-streams.h"
 #include "src/simulator.h"
 #include "src/snapshot.h"
@@ -6691,6 +6692,13 @@ void Isolate::GetHeapStatistics(HeapStatistics* heap_statistics) {
 }
 
 
+size_t Isolate::GetStackSample(const RegisterState& state, void** frames,
+                               size_t frames_limit) {
+  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
+  return i::TickSample::GetStackSample(isolate, state, frames, frames_limit);
+}
+
+
 void Isolate::SetEventLogger(LogEventCallback that) {
   // Do not overwrite the event logger if we want to log explicitly.
   if (i::FLAG_log_timer_events) return;