Fuchsia: Fixes for Debug build

runtime/vm/os_thread_fuchsia.cc

 // Copyright (c) 2016, 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_FUCHSIA)
 
 #include "vm/os_thread.h"
 #include "vm/os_thread_fuchsia.h"
 
@@ skipping 151 matching lines @@
 }
 
 
 ThreadId OSThread::GetCurrentThreadId() {
   return pthread_self();
 }
 
 
 #ifndef PRODUCT
 ThreadId OSThread::GetCurrentThreadTraceId() {
-  UNIMPLEMENTED();
-  return 0;
+  return pthread_self();
 }
 #endif  // PRODUCT
 
 
 ThreadJoinId OSThread::GetCurrentThreadJoinId(OSThread* thread) {
   ASSERT(thread != NULL);
   // Make sure we're filling in the join id for the current thread.
   ASSERT(thread->id() == GetCurrentThreadId());
   // Make sure the join_id_ hasn't been set, yet.
   DEBUG_ASSERT(thread->join_id_ == kInvalidThreadJoinId);
@@ skipping 243 matching lines @@
 void Monitor::NotifyAll() {
   // When running with assertions enabled we track the owner.
   ASSERT(IsOwnedByCurrentThread());
   int result = pthread_cond_broadcast(data_.cond());
   VALIDATE_PTHREAD_RESULT(result);
 }
 
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_FUCHSIA)