Always close epoll/kqueue file descriptor (#2723)

Resolves #2643, resolves #2721

src/browser/NativeMessagingBase.cpp

@@ -65,6 +65,7 @@ void NativeMessagingBase::newNativeMessage()
     EV_SET(ev, fileno(stdin), EVFILT_READ, EV_ADD, 0, 0, nullptr);
     if (kevent(fd, ev, 1, nullptr, 0, &ts) == -1) {
         m_notifier->setEnabled(false);
+        ::close(fd);
         return;
     }
 
@@ -81,6 +82,7 @@ void NativeMessagingBase::newNativeMessage()
     event.data.fd = 0;
     if (epoll_ctl(fd, EPOLL_CTL_ADD, 0, &event) != 0) {
         m_notifier->setEnabled(false);
+        ::close(fd);
         return;
     }