base: Support setting thread priorities generically.

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/lazy_instance.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
 #include "base/threading/thread_id_name_manager.h"
@@ skipping 130 matching lines @@
     return;
 
   stopping_ = true;
   message_loop_->PostTask(FROM_HERE, base::Bind(&ThreadQuitHelper));
 }
 
 bool Thread::IsRunning() const {
   return running_;
 }
 
+void Thread::SetPriority(ThreadPriority priority) {
+  // The thread must be started (and id known) for this to be
+  // compatible with all platforms.
+  DCHECK_NE(thread_id_, kInvalidThreadId);
+  PlatformThread::SetThreadPriority(thread_, priority);
+}
+
 void Thread::Run(MessageLoop* message_loop) {
   message_loop->Run();
 }
 
 void Thread::SetThreadWasQuitProperly(bool flag) {
   lazy_tls_bool.Pointer()->Set(flag);
 }
 
 bool Thread::GetThreadWasQuitProperly() {
   bool quit_properly = true;
@@ skipping 45 matching lines @@
 
     // Assert that MessageLoop::Quit was called by ThreadQuitHelper.
     DCHECK(GetThreadWasQuitProperly());
 
     // We can't receive messages anymore.
     message_loop_ = NULL;
   }
 }
 
 }  // namespace base