Reland 66791 (change was innocent)...

base/platform_thread_win.cc

Index: base/platform_thread_win.cc
===================================================================
--- base/platform_thread_win.cc	(revision 66806)
+++ base/platform_thread_win.cc	(working copy)
@@ -5,6 +5,7 @@
 #include "base/platform_thread.h"
 
 #include "base/logging.h"
+#include "base/thread_restrictions.h"
 #include "base/win/windows_version.h"
 
 namespace {
@@ -20,13 +21,58 @@
   DWORD dwFlags;  // Reserved for future use, must be zero.
 } THREADNAME_INFO;
 
-DWORD __stdcall ThreadFunc(void* closure) {
-  PlatformThread::Delegate* delegate =
-      static_cast<PlatformThread::Delegate*>(closure);
+struct ThreadParams {
+  PlatformThread::Delegate* delegate;
+  bool joinable;
+};
+
+DWORD __stdcall ThreadFunc(void* params) {
+  ThreadParams* thread_params = static_cast<ThreadParams*>(params);
+  PlatformThread::Delegate* delegate = thread_params->delegate;
+  if (!thread_params->joinable)
+    base::ThreadRestrictions::SetSingletonAllowed(false);
+  delete thread_params;
   delegate->ThreadMain();
   return NULL;
 }
 
+// CreateThreadInternal() matches PlatformThread::Create(), except that
+// |out_thread_handle| may be NULL, in which case a non-joinable thread is
+// created.
+bool CreateThreadInternal(size_t stack_size,
+                          PlatformThread::Delegate* delegate,
+                          PlatformThreadHandle* out_thread_handle) {
+  PlatformThreadHandle thread_handle;
+  unsigned int flags = 0;
+  if (stack_size > 0 && base::win::GetVersion() >= base::win::VERSION_XP) {
+    flags = STACK_SIZE_PARAM_IS_A_RESERVATION;
+  } else {
+    stack_size = 0;
+  }
+
+  ThreadParams* params = new ThreadParams;
+  params->delegate = delegate;
+  params->joinable = out_thread_handle != NULL;
+
+  // Using CreateThread here vs _beginthreadex makes thread creation a bit
+  // faster and doesn't require the loader lock to be available.  Our code will
+  // have to work running on CreateThread() threads anyway, since we run code
+  // on the Windows thread pool, etc.  For some background on the difference:
+  //   http://www.microsoft.com/msj/1099/win32/win321099.aspx
+  thread_handle = CreateThread(
+      NULL, stack_size, ThreadFunc, params, flags, NULL);
+  if (!thread_handle) {
+    delete params;
+    return false;
+  }
+
+  if (out_thread_handle)
+    *out_thread_handle = thread_handle;
+  else
+    CloseHandle(thread_handle);
+  return true;
+}
+
 }  // namespace
 
 // static
@@ -67,29 +113,13 @@
 // static
 bool PlatformThread::Create(size_t stack_size, Delegate* delegate,
                             PlatformThreadHandle* thread_handle) {
-  unsigned int flags = 0;
-  if (stack_size > 0 && base::win::GetVersion() >= base::win::VERSION_XP) {
-    flags = STACK_SIZE_PARAM_IS_A_RESERVATION;
-  } else {
-    stack_size = 0;
-  }
-
-  // Using CreateThread here vs _beginthreadex makes thread creation a bit
-  // faster and doesn't require the loader lock to be available.  Our code will
-  // have to work running on CreateThread() threads anyway, since we run code
-  // on the Windows thread pool, etc.  For some background on the difference:
-  //   http://www.microsoft.com/msj/1099/win32/win321099.aspx
-  *thread_handle = CreateThread(
-      NULL, stack_size, ThreadFunc, delegate, flags, NULL);
-  return *thread_handle != NULL;
+  DCHECK(thread_handle);
+  return CreateThreadInternal(stack_size, delegate, thread_handle);
 }
 
 // static
 bool PlatformThread::CreateNonJoinable(size_t stack_size, Delegate* delegate) {
-  PlatformThreadHandle thread_handle;
-  bool result = Create(stack_size, delegate, &thread_handle);
-  CloseHandle(thread_handle);
-  return result;
+  return CreateThreadInternal(stack_size, delegate, NULL);
 }
 
 // static