Use platform implementation of Monitor in thread pool

runtime/bin/thread_pool_win.cc

Index: runtime/bin/thread_pool_win.cc
diff --git a/runtime/bin/thread_pool_win.cc b/runtime/bin/thread_pool_win.cc
index cca9fc8d0d757ea4444e436132005501c76b15bf..cf6b860e76b44c0f80afe4857fe8c0e39dc413a3 100644
--- a/runtime/bin/thread_pool_win.cc
+++ b/runtime/bin/thread_pool_win.cc
@@ -4,27 +4,6 @@
 
 #include "bin/thread_pool.h"
 
-TaskQueue::TaskQueue() : terminate_(false), head_(NULL), tail_(NULL) {
-  UNIMPLEMENTED();
-}
-
-
-void TaskQueue::Insert(TaskQueueEntry* entry) {
-  UNIMPLEMENTED();
-}
-
-
-void TaskQueue::Shutdown() {
-  UNIMPLEMENTED();
-}
-
-
-TaskQueueEntry* TaskQueue::Remove() {
-  UNIMPLEMENTED();
-  return NULL;
-}
-
-
 void ThreadPool::Start() {
   UNIMPLEMENTED();
 }