Uses an open thread handle as the ThreadJoinId on Windows.

runtime/bin/thread_win.cc

Index: runtime/bin/thread_win.cc
diff --git a/runtime/bin/thread_win.cc b/runtime/bin/thread_win.cc
index db4119604000d64ae30868b7fb32514ae9e30212..92a9801fa07ea38b48396677852fb63ca09bb20c 100644
--- a/runtime/bin/thread_win.cc
+++ b/runtime/bin/thread_win.cc
@@ -103,27 +103,6 @@ ThreadId Thread::GetCurrentThreadId() {
 }
 
 
-bool Thread::Join(ThreadId id) {
-  HANDLE handle = OpenThread(SYNCHRONIZE, false, id);
-
-  // TODO(zra): OSThread::Start() closes the handle to the thread. Thus, by the
-  // time we try to join the thread, its resources may have already been
-  // reclaimed, and joining will fail. This can be avoided in a couple of ways.
-  // First, GetCurrentThreadJoinId could call OpenThread and return a handle.
-  // This is bad, because each of those handles would have to be closed.
-  // Second OSThread could be refactored to no longer be AllStatic. Then the
-  // handle could be cached in the object by the Start method.
-  if (handle == NULL) {
-    return false;
-  }
-
-  DWORD res = WaitForSingleObject(handle, INFINITE);
-  CloseHandle(handle);
-  ASSERT(res == WAIT_OBJECT_0);
-  return true;
-}
-
-
 intptr_t Thread::ThreadIdToIntPtr(ThreadId id) {
   ASSERT(sizeof(id) <= sizeof(intptr_t));
   return static_cast<intptr_t>(id);