Fix crash with MIDI send for MidiManagerAlsa

media/midi/midi_manager.cc

Index: media/midi/midi_manager.cc
diff --git a/media/midi/midi_manager.cc b/media/midi/midi_manager.cc
index 6e8c1a266fa86502407d929db218eb1e85afc1f5..27fe9c6eb21b668971ea659e61650005d4fb9f54 100644
--- a/media/midi/midi_manager.cc
+++ b/media/midi/midi_manager.cc
@@ -134,11 +134,10 @@ void MidiManager::EndSession(MidiManagerClient* client) {
 }
 
 void MidiManager::AccumulateMidiBytesSent(MidiManagerClient* client, size_t n) {
-  {
-    base::AutoLock auto_lock(lock_);
-    if (clients_.find(client) == clients_.end())
-      return;
-  }
+  base::AutoLock auto_lock(lock_);
+  if (clients_.find(client) == clients_.end())
+    return;
+
   client->AccumulateMidiBytesSent(n);
 }