Introduce PlatformThread::Detach

base/threading/platform_thread_win.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/platform_thread.h"
 
 #include <stddef.h>
 
 #include "base/debug/alias.h"
 #include "base/debug/profiler.h"
@@ skipping 201 matching lines @@
   // the thread referred to by |thread_handle| may still be running long-lived /
   // blocking tasks.
 #if 0
   base::ThreadRestrictions::AssertIOAllowed();
 #endif
 
   // Wait for the thread to exit.  It should already have terminated but make
   // sure this assumption is valid.
   DWORD result = WaitForSingleObject(thread_handle.platform_handle(), INFINITE);
   if (result != WAIT_OBJECT_0) {
     // Debug info for bug 127931.

[danakj, 2016/06/09 22:58:07]

Oh fun, this bug is fixed, maybe you can clean this up, and change the CHECK to
a DCHECK again? (maybe in another CL?)

[robliao, 2016/06/10 14:24:31]

Clean up done at https://codereview.chromium.org/2053393002/

We should keep this as a CHECK similar to POSIX, as failing to join is quite
bad.

     DWORD error = GetLastError();
     debug::Alias(&error);
     debug::Alias(&result);
     CHECK(false);
   }
 
   CloseHandle(thread_handle.platform_handle());
 }
 
 // static
+void PlatformThread::Detach(PlatformThreadHandle thread_handle) {
+  CloseHandle(thread_handle.platform_handle());
+}
+
+// static
 void PlatformThread::SetCurrentThreadPriority(ThreadPriority priority) {
   int desired_priority = THREAD_PRIORITY_ERROR_RETURN;
   switch (priority) {
     case ThreadPriority::BACKGROUND:
       desired_priority = THREAD_PRIORITY_LOWEST;
       break;
     case ThreadPriority::NORMAL:
       desired_priority = THREAD_PRIORITY_NORMAL;
       break;
     case ThreadPriority::DISPLAY:
@@ skipping 32 matching lines @@
       return ThreadPriority::REALTIME_AUDIO;
     case THREAD_PRIORITY_ERROR_RETURN:
       DPCHECK(false) << "GetThreadPriority error";  // Falls through.
     default:
       NOTREACHED() << "Unexpected priority: " << priority;
       return ThreadPriority::NORMAL;
   }
 }
 
 }  // namespace base