diff -r 490d5cc509ed -r cf61fcea0001 wp/wp-includes/customize/class-wp-customize-site-icon-control.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/customize/class-wp-customize-site-icon-control.php	Mon Oct 14 17:39:30 2019 +0200
@@ -0,0 +1,98 @@
+<?php
+/**
+ * Customize API: WP_Customize_Site_Icon_Control class
+ *
+ * @package WordPress
+ * @subpackage Customize
+ * @since 4.4.0
+ */
+
+/**
+ * Customize Site Icon control class.
+ *
+ * Used only for custom functionality in JavaScript.
+ *
+ * @since 4.3.0
+ *
+ * @see WP_Customize_Cropped_Image_Control
+ */
+class WP_Customize_Site_Icon_Control extends WP_Customize_Cropped_Image_Control {
+
+	/**
+	 * Control type.
+	 *
+	 * @since 4.3.0
+	 * @var string
+	 */
+	public $type = 'site_icon';
+
+	/**
+	 * Constructor.
+	 *
+	 * @since 4.3.0
+	 *
+	 * @param WP_Customize_Manager $manager Customizer bootstrap instance.
+	 * @param string               $id      Control ID.
+	 * @param array                $args    Optional. Arguments to override class property defaults.
+	 */
+	public function __construct( $manager, $id, $args = array() ) {
+		parent::__construct( $manager, $id, $args );
+		add_action( 'customize_controls_print_styles', 'wp_site_icon', 99 );
+	}
+
+	/**
+	 * Renders a JS template for the content of the site icon control.
+	 *
+	 * @since 4.5.0
+	 */
+	public function content_template() {
+		?>
+		<label for="{{ data.settings['default'] }}-button">
+			<# if ( data.label ) { #>
+				<span class="customize-control-title">{{ data.label }}</span>
+			<# } #>
+			<# if ( data.description ) { #>
+				<span class="description customize-control-description">{{{ data.description }}}</span>
+			<# } #>
+		</label>
+
+		<# if ( data.attachment && data.attachment.id ) { #>
+			<div class="attachment-media-view">
+				<# if ( data.attachment.sizes ) { #>
+					<div class="site-icon-preview wp-clearfix">
+						<div class="favicon-preview">
+							<img src="<?php echo esc_url( admin_url( 'images/' . ( is_rtl() ? 'browser-rtl.png' : 'browser.png' ) ) ); ?>" class="browser-preview" width="182" alt="" />
+
+							<div class="favicon">
+								<img src="{{ data.attachment.sizes.full ? data.attachment.sizes.full.url : data.attachment.url }}" alt="<?php esc_attr_e( 'Preview as a browser icon' ); ?>"/>
+							</div>
+							<span class="browser-title" aria-hidden="true"><?php bloginfo( 'name' ); ?></span>
+						</div>
+						<img class="app-icon-preview" src="{{ data.attachment.sizes.full ? data.attachment.sizes.full.url : data.attachment.url }}" alt="<?php esc_attr_e( 'Preview as an app icon' ); ?>"/>
+					</div>
+				<# } #>
+				<div class="actions">
+					<# if ( data.canUpload ) { #>
+						<button type="button" class="button remove-button"><?php echo $this->button_labels['remove']; ?></button>
+						<button type="button" class="button upload-button" id="{{ data.settings['default'] }}-button"><?php echo $this->button_labels['change']; ?></button>
+					<# } #>
+				</div>
+			</div>
+		<# } else { #>
+			<div class="attachment-media-view">
+				<div class="placeholder">
+					<?php echo $this->button_labels['placeholder']; ?>
+				</div>
+				<div class="actions">
+					<# if ( data.defaultAttachment ) { #>
+						<button type="button" class="button default-button"><?php echo $this->button_labels['default']; ?></button>
+					<# } #>
+					<# if ( data.canUpload ) { #>
+						<button type="button" class="button upload-button" id="{{ data.settings['default'] }}-button"><?php echo $this->button_labels['select']; ?></button>
+					<# } #>
+				</div>
+			</div>
+		<# } #>
+		<?php
+	}
+}