[WIP] A sampler thread in d8 for consuming the new API.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 8bdf26f4c27bbb4bd063196b0be3ad76d6552d6f..43b867bafcd6384d55f893e52174cb9de21cc718 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -34,9 +34,9 @@
 #endif
 
 #include "src/d8.h"
+#include "src/api.h"
 
 #ifndef V8_SHARED
-#include "src/api.h"
 #include "src/base/cpu.h"
 #include "src/base/logging.h"
 #include "src/base/platform/platform.h"
@@ -46,6 +46,8 @@
 #include "src/v8.h"
 #endif  // !V8_SHARED
 
+#include "src/sampler-thread.h"
+
 #if !defined(_WIN32) && !defined(_WIN64)
 #include <unistd.h>  // NOLINT
 #endif
@@ -1158,6 +1160,7 @@ void SourceGroup::Execute(Isolate* isolate) {
     } else if (arg[0] == '-') {
       // Ignore other options. They have been parsed already.
     } else {
+      v8::SamplerThread* sampler = new SamplerThread(isolate);
       // Use all other arguments as names of files to load and run.
       HandleScope handle_scope(isolate);
       Handle<String> file_name = String::NewFromUtf8(isolate, arg);
@@ -1166,10 +1169,12 @@ void SourceGroup::Execute(Isolate* isolate) {
         printf("Error reading '%s'\n", arg);
         Shell::Exit(1);
       }
+      sampler->Start();
       if (!Shell::ExecuteString(isolate, source, file_name, false, true)) {
         exception_was_thrown = true;
         break;
       }
+      sampler->Stop();
     }
   }
   if (exception_was_thrown != Shell::options.expected_to_throw) {
@@ -1365,6 +1370,8 @@ bool Shell::SetOptions(int argc, char* argv[]) {
 
 
 int Shell::RunMain(Isolate* isolate, int argc, char* argv[]) {
+  v8::SamplerThread* sampler = new SamplerThread(isolate);
+  delete sampler;
 #ifndef V8_SHARED
   for (int i = 1; i < options.num_isolates; ++i) {
     options.isolate_sources[i].StartExecuteInThread();