If JavaScript shows a dialog, cause the page to lose fullscreen.

BUG=670135, 550017, 726761, 728276

Review-Url: https://codereview.chromium.org/2906133004
Cr-Commit-Position: refs/heads/master@{#478884}
void PrintViewManager::OnDidShowPrintDialog(content::RenderFrameHost* rfh) {
  if (rfh != print_preview_rfh_)
    return;

  if (on_print_dialog_shown_callback_.is_null())
    return;

  on_print_dialog_shown_callback_.Run();
  on_print_dialog_shown_callback_.Reset();
}

void PrintViewManager::OnDidShowPrintDialog(content::RenderFrameHost* rfh) {
  if (rfh != print_preview_rfh_)
    return;

  if (on_print_dialog_shown_callback_.is_null())
    return;

  on_print_dialog_shown_callback_.Run();
  on_print_dialog_shown_callback_.Reset();
}
