Quit the message loop by default in ShellConnectionLost when ApplicationRunner is used

components/leveldb/leveldb_app.cc

Index: components/leveldb/leveldb_app.cc
diff --git a/components/leveldb/leveldb_app.cc b/components/leveldb/leveldb_app.cc
index ac2855fa32f357093b8fc63b0f30589d8ad00792..e21639107c3743f38dfaa82f0bf510ddebe0b825 100644
--- a/components/leveldb/leveldb_app.cc
+++ b/components/leveldb/leveldb_app.cc
@@ -25,11 +25,6 @@ bool LevelDBApp::AcceptConnection(mojo::Connection* connection) {
   return true;
 }
 
-void LevelDBApp::ShellConnectionLost() {
-  // TODO: This should exit cleanly.
-  _exit(1);
-}
-
 void LevelDBApp::Create(mojo::Connection* connection,
                         leveldb::LevelDBServiceRequest request) {
   if (!service_)