Replace IOAllowed with WaitAllowed in PlatformThread::Join()

base/threading/platform_thread_win.cc

Index: base/threading/platform_thread_win.cc
diff --git a/base/threading/platform_thread_win.cc b/base/threading/platform_thread_win.cc
index e271fe8225545e14db5738f9cb8a7f9c7dd1d7cf..289aebf9b78edaf4b374d881e3a928a435b998fa 100644
--- a/base/threading/platform_thread_win.cc
+++ b/base/threading/platform_thread_win.cc
@@ -225,18 +225,15 @@ bool PlatformThread::CreateNonJoinableWithPriority(size_t stack_size,
 
 // static
 void PlatformThread::Join(PlatformThreadHandle thread_handle) {
-  // Record the event that this thread is blocking upon (for hang diagnosis).
-  base::debug::ScopedThreadJoinActivity thread_activity(&thread_handle);
-
   DCHECK(thread_handle.platform_handle());
-  // TODO(willchan): Enable this check once I can get it to work for Windows
-  // shutdown.
+
   // Joining another thread may block the current thread for a long time, since
   // the thread referred to by |thread_handle| may still be running long-lived /
   // blocking tasks.
-#if 0
-  base::ThreadRestrictions::AssertIOAllowed();
-#endif
+  base::ThreadRestrictions::AssertWaitAllowed();
+
+  // Record the event that this thread is blocking upon (for hang diagnosis).
+  base::debug::ScopedThreadJoinActivity thread_activity(&thread_handle);
 
   // Wait for the thread to exit.  It should already have terminated but make
   // sure this assumption is valid.