Gtk3: Silence deprecation warnings in //remoting

remoting/host/continue_window_linux.cc

Index: remoting/host/continue_window_linux.cc
diff --git a/remoting/host/continue_window_linux.cc b/remoting/host/continue_window_linux.cc
index 3bc85424fcb27ea7c78c0ba3d85c7c5fb7d5b0f3..bdbe724485f1c2c5a8206b695839007d95824d43 100644
--- a/remoting/host/continue_window_linux.cc
+++ b/remoting/host/continue_window_linux.cc
@@ -102,7 +102,9 @@ void ContinueWindowGtk::CreateWindow() {
       gtk_label_new(l10n_util::GetStringUTF8(IDS_CONTINUE_PROMPT).c_str());
   gtk_label_set_line_wrap(GTK_LABEL(text_label), TRUE);
   // TODO(lambroslambrou): Fix magic numbers, as in disconnect_window_gtk.cc.
+  G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
   gtk_misc_set_padding(GTK_MISC(text_label), 12, 12);
+  G_GNUC_END_IGNORE_DEPRECATIONS;
   gtk_container_add(GTK_CONTAINER(content_area), text_label);
 
   gtk_widget_show_all(content_area);