Weaken an assert in the message handler

runtime/vm/os_thread_win.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"  // NOLINT
 #if defined(TARGET_OS_WINDOWS)
 
 #include "vm/os_thread.h"
 
 #include <process.h>  // NOLINT
@@ skipping 100 matching lines @@
   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) {
-    ASSERT(GetLastError() == ERROR_INVALID_PARAMETER);
     return;
   }
 
   DWORD res = WaitForSingleObject(handle, INFINITE);
   CloseHandle(handle);
   ASSERT(res == WAIT_OBJECT_0);
 }
 
 
 intptr_t OSThread::ThreadIdToIntPtr(ThreadId id) {
@@ skipping 340 matching lines @@
   // timeout before we signal it, that object will get an extra
   // signal. This will be treated as a spurious wake-up and is OK
   // since all uses of monitors should recheck the condition after a
   // Wait.
   data_.SignalAndRemoveAllWaiters();
 }
 
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_WINDOWS)