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

webrtc/base/platform_thread.cc

Index: webrtc/base/platform_thread.cc
diff --git a/webrtc/base/platform_thread.cc b/webrtc/base/platform_thread.cc
index 286bee95f1299823920ec03175962dbf61e9cba8..0b025f2af048f94d9e776f171276850f54ef952e 100644
--- a/webrtc/base/platform_thread.cc
+++ b/webrtc/base/platform_thread.cc
@@ -119,6 +119,11 @@ PlatformThread::~PlatformThread() {
 
 #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;
 }