Exempt the Service Thread from BLOCK_SHUTDOWN DCHECKs

base/threading/thread.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/threading/thread.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
@@ skipping 207 matching lines @@
   owning_sequence_checker_.DetachFromSequence();
 }
 
 PlatformThreadId Thread::GetThreadId() const {
   // If the thread is created but not started yet, wait for |id_| being ready.
   base::ThreadRestrictions::ScopedAllowWait allow_wait;
   id_event_.Wait();
   return id_;
 }
 
+PlatformThreadHandle Thread::GetThreadHandle() const {
+  AutoLock lock(thread_lock_);
+  return thread_;
+}
+
 bool Thread::IsRunning() const {
   // TODO(gab): Fix improper usage of this API (http://crbug.com/629139) and
   // enable this check.
   // DCHECK(owning_sequence_checker_.CalledOnValidSequence());
 
   // If the thread's already started (i.e. |message_loop_| is non-null) and not
   // yet requested to stop (i.e. |stopping_| is false) we can just return true.
   // (Note that |stopping_| is touched only on the same sequence that starts /
   // started the new thread so we need no locking here.)
   if (message_loop_ && !stopping_)
@@ skipping 119 matching lines @@
   run_loop_ = nullptr;
 }
 
 void Thread::ThreadQuitHelper() {
   DCHECK(run_loop_);
   run_loop_->QuitWhenIdle();
   SetThreadWasQuitProperly(true);
 }
 
 }  // namespace base