WP_Customize_Manager::get_messenger_channel PHP Method

    public function get_messenger_channel()
    {
        return $this->messenger_channel;
    }

 /**
  * Test WP_Customize_Manager::__construct().
  *
  * @covers WP_Customize_Manager::__construct()
  */
 function test_constructor()
 {
     $uuid = wp_generate_uuid4();
     $theme = 'twentyfifteen';
     $messenger_channel = 'preview-123';
     $wp_customize = new WP_Customize_Manager(array('changeset_uuid' => $uuid, 'theme' => $theme, 'messenger_channel' => $messenger_channel));
     $this->assertEquals($uuid, $wp_customize->changeset_uuid());
     $this->assertEquals($theme, $wp_customize->get_stylesheet());
     $this->assertEquals($messenger_channel, $wp_customize->get_messenger_channel());
     $theme = 'twentyfourteen';
     $messenger_channel = 'preview-456';
     $_REQUEST['theme'] = $theme;
     $_REQUEST['customize_messenger_channel'] = $messenger_channel;
     $wp_customize = new WP_Customize_Manager(array('changeset_uuid' => $uuid));
     $this->assertEquals($theme, $wp_customize->get_stylesheet());
     $this->assertEquals($messenger_channel, $wp_customize->get_messenger_channel());
     $theme = 'twentyfourteen';
     $_REQUEST['customize_theme'] = $theme;
     $wp_customize = new WP_Customize_Manager();
     $this->assertEquals($theme, $wp_customize->get_stylesheet());
     $this->assertNotEmpty($wp_customize->changeset_uuid());
 }