Clean up verbose logging.

Change-Id: I6b01980e7145c4f8d25a5b50f620903f61a1b427
diff --git a/src/logging.cc b/src/logging.cc
index 34e5e8d..4f1ae55 100644
--- a/src/logging.cc
+++ b/src/logging.cc
@@ -22,6 +22,8 @@
 
 namespace art {
 
+LogVerbosity gLogVerbosity;
+
 art::Mutex& GetLoggingLock() {
   static art::Mutex lock("LogMessage lock");
   return lock;