Cloning panels results in "Warning: implode() [function.implode]: Invalid arguments passed in form_error"

I attempted to clone a panel and after displaying the cloned panel in a view result, I initially got the following error:

Warning: implode() [function.implode]: Invalid arguments passed in form_error() (line 1645 of /path-to-site/includes/form.inc).
Notice: Undefined index: layout in panels_node_hook_insert() (line 273 of /path-to-site/sites/all/modules/panels/panels_node/panels_node.module).

After refreshing the view output (without making changes) I got this error:

Notice: Undefined index: theme in panels_renderer_standard->render_layout() (line 392 of /path-to-site/sites/all/modules/panels/plugins/display_renderers/panels_renderer_standard.class.php).

Relevant code (lines 381-393 of panels_renderer_standard.class.php):

  function render_layout() {
    if (empty($this->prep_run)) {
      $this->prepare();
    }
    $this->render_panes();
    $this->render_regions();

    if ($this->admin && !empty($this->plugins['layout']['admin theme'])) {
      $theme = $this->plugins['layout']['admin theme'];
    }
    else {
      $theme = $this->plugins['layout']['theme'];
    }

Is this issue a Views, Panels or a Node clone issue?