Fix memory leak from d8 shell.

src/d8.h

Index: src/d8.h
diff --git a/src/d8.h b/src/d8.h
index 28321f56dae720dd2e02d56881132966f53921c7..c9cf1b4e5da503394c5db14a16ef1eb6c22cac4e 100644
--- a/src/d8.h
+++ b/src/d8.h
@@ -28,11 +28,11 @@
 #ifndef V8_D8_H_
 #define V8_D8_H_
 
-
 #ifndef V8_SHARED
-#include "v8.h"
 #include "allocation.h"
 #include "hashmap.h"
+#include "smart-pointer.h"
+#include "v8.h"
 #else
 #include "../include/v8.h"
 #endif  // V8_SHARED
@@ -122,11 +122,10 @@ class SourceGroup {
 #ifndef V8_SHARED
       next_semaphore_(v8::internal::OS::CreateSemaphore(0)),
       done_semaphore_(v8::internal::OS::CreateSemaphore(0)),
-      thread_(NULL),
 #endif  // V8_SHARED
       argv_(NULL),
       begin_offset_(0),
-      end_offset_(0) { }
+      end_offset_(0) {}
 
   void Begin(char** argv, int offset) {
     argv_ = const_cast<const char**>(argv);
@@ -158,9 +157,9 @@ class SourceGroup {
   static i::Thread::Options GetThreadOptions();
   void ExecuteInThread();
 
-  i::Semaphore* next_semaphore_;
-  i::Semaphore* done_semaphore_;
-  i::Thread* thread_;
+  i::SmartPointer<i::Semaphore> next_semaphore_;
+  i::SmartPointer<i::Semaphore> done_semaphore_;
+  i::SmartPointer<i::Thread> thread_;
 #endif  // V8_SHARED
 
   void ExitShell(int exit_code);