Cleanup Semaphore class.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 4a10550088fb90e0c3e8783558737fce2a202873..6f41dc423c6fba3d449391894e5cc92bf61223db 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -1220,10 +1220,6 @@ void ShellThread::Run() {
 
 SourceGroup::~SourceGroup() {
 #ifndef V8_SHARED
-  delete next_semaphore_;
-  next_semaphore_ = NULL;
-  delete done_semaphore_;
-  done_semaphore_ = NULL;
   delete thread_;
   thread_ = NULL;
 #endif  // V8_SHARED
@@ -1284,7 +1280,7 @@ i::Thread::Options SourceGroup::GetThreadOptions() {
 void SourceGroup::ExecuteInThread() {
   Isolate* isolate = Isolate::New();
   do {
-    if (next_semaphore_ != NULL) next_semaphore_->Wait();
+    next_semaphore_.Wait();
     {
       Isolate::Scope iscope(isolate);
       Locker lock(isolate);
@@ -1304,7 +1300,7 @@ void SourceGroup::ExecuteInThread() {
         V8::IdleNotification(kLongIdlePauseInMs);
       }
     }
-    if (done_semaphore_ != NULL) done_semaphore_->Signal();
+    done_semaphore_.Signal();
   } while (!Shell::options.last_run);
   isolate->Dispose();
 }
@@ -1315,7 +1311,7 @@ void SourceGroup::StartExecuteInThread() {
     thread_ = new IsolateThread(this);
     thread_->Start();
   }
-  next_semaphore_->Signal();
+  next_semaphore_.Signal();
 }
 
 
@@ -1324,7 +1320,7 @@ void SourceGroup::WaitForThread() {
   if (Shell::options.last_run) {
     thread_->Join();
   } else {
-    done_semaphore_->Wait();
+    done_semaphore_.Wait();
   }
 }
 #endif  // V8_SHARED