Make sure GetLastError on a PlatformThread return an error that is relevant to the thread.

webrtc/base/platform_thread.cc

 /*
  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 101 matching lines @@
 PlatformThread::~PlatformThread() {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
 #if defined(WEBRTC_WIN)
   RTC_DCHECK(!thread_);
   RTC_DCHECK(!thread_id_);
 #endif  // defined(WEBRTC_WIN)
 }
 
 #if defined(WEBRTC_WIN)
 DWORD WINAPI PlatformThread::StartThread(void* param) {
+  // The GetLastError() function only returns valid results when it is called
+  // after a Win32 API function that returns a "failed" result. A crash dump
+  // contains the result from GetLastError() and to make sure it does not
+  // falsely report a Windows error we call SetLastError here.
+  ::SetLastError(ERROR_SUCCESS);
   static_cast<PlatformThread*>(param)->Run();
   return 0;
 }
 #else
 void* PlatformThread::StartThread(void* param) {
   static_cast<PlatformThread*>(param)->Run();
   return 0;
 }
 #endif  // defined(WEBRTC_WIN)
 
@@ skipping 131 matching lines @@
 #if defined(WEBRTC_WIN)
 bool PlatformThread::QueueAPC(PAPCFUNC function, ULONG_PTR data) {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
   RTC_DCHECK(IsRunning());
 
   return QueueUserAPC(function, thread_, data) != FALSE;
 }
 #endif
 
 }  // namespace rtc