During upgrade to the Chromium 61 we have switched from GTK2 to GTK3
and now we have a few warnings about stuff being deprecated in GTK3.
Check any Linux build to get a list of them.

/cc @zcbenz 
atom/browser/ui/file_dialog_gtk.cc
#include "atom/browser/ui/file_dialog.h"
#include "atom/browser/native_window_views.h"
#include "atom/browser/unresponsive_suppressor.h"
#include "base/callback.h"
#include "base/files/file_util.h"
#include "base/strings/string_util.h"
#include "chrome/browser/ui/libgtkui/gtk_signal.h"
#include "chrome/browser/ui/libgtkui/gtk_util.h"
#include "ui/views/widget/desktop_aura/x11_desktop_handler.h"
namespace file_dialog {
namespace {
gboolean FileFilterCaseInsensitive(const GtkFileFilterInfo* file_info,
                                   std::string* file_extension) {
  
  if (*file_extension == ".*")
    return true;
  return base::EndsWith(
    file_info->filename,
    *file_extension, base::CompareCase::INSENSITIVE_ASCII);
}
void OnFileFilterDataDestroyed(std::string* file_extension) {
  delete file_extension;
}
class FileChooserDialog {