Remove static initializer in dummy_event

ipc/ipc_sync_message.cc

Index: ipc/ipc_sync_message.cc
diff --git a/ipc/ipc_sync_message.cc b/ipc/ipc_sync_message.cc
index e276263458f3c228d4644647b50274a766646552..3b093ae52fe7109069bd378e1d83ce0abc451ef7 100644
--- a/ipc/ipc_sync_message.cc
+++ b/ipc/ipc_sync_message.cc
@@ -20,8 +20,6 @@ namespace IPC {
 
 static base::AtomicSequenceNumber g_next_id(base::LINKER_INITIALIZED);
 
-static base::WaitableEvent* dummy_event = new base::WaitableEvent(true, true);
-
 SyncMessage::SyncMessage(
     int32 routing_id,
     uint32 type,
@@ -50,6 +48,7 @@ MessageReplyDeserializer* SyncMessage::GetReplyDeserializer() {
 
 void SyncMessage::EnableMessagePumping() {
   DCHECK(!pump_messages_event_);
+  static base::WaitableEvent* dummy_event = new base::WaitableEvent(true, true);

[jam, 2012/01/27 18:19:04]

I don't believe this is thread safe, i.e. if it's called by two threads at the
same time two objects can be created.

[Tyler Breisacher (Chromium), 2012/01/30 22:58:03]

Right, sorry. What do you think is the right way to handle this case?

[jam, 2012/02/01 17:01:20]

use LazyInstance. it's thread-safe

   set_pump_messages_event(dummy_event);
 }