--- a/wp/wp-admin/custom-background.php	Mon Jun 08 16:11:51 2015 +0000
+++ b/wp/wp-admin/custom-background.php	Tue Jun 09 03:35:32 2015 +0200
@@ -20,27 +20,21 @@
 	 *
 	 * @var callback
 	 * @since 3.0.0
-	 * @access private
 	 */
-	var $admin_header_callback;
+	public $admin_header_callback;
 
 	/**
 	 * Callback for header div.
 	 *
 	 * @var callback
 	 * @since 3.0.0
-	 * @access private
 	 */
-	var $admin_image_div_callback;
+	public $admin_image_div_callback;
 
 	/**
-	 * Holds the page menu hook.
-	 *
-	 * @var string
-	 * @since 3.0.0
-	 * @access private
+	 * @var bool
 	 */
-	var $page = '';
+	private $updated;
 
 	/**
 	 * Constructor - Register administration header callback.
@@ -48,13 +42,16 @@
 	 * @since 3.0.0
 	 * @param callback $admin_header_callback
 	 * @param callback $admin_image_div_callback Optional custom image div output callback.
-	 * @return Custom_Background
 	 */
-	function __construct($admin_header_callback = '', $admin_image_div_callback = '') {
+	public function __construct($admin_header_callback = '', $admin_image_div_callback = '') {
 		$this->admin_header_callback = $admin_header_callback;
 		$this->admin_image_div_callback = $admin_image_div_callback;
 
 		add_action( 'admin_menu', array( $this, 'init' ) );
+
+		add_action( 'wp_ajax_custom-background-add', array( $this, 'ajax_background_add' ) );
+
+		// Unused since 3.5.0.
 		add_action( 'wp_ajax_set-background-image', array( $this, 'wp_set_background_image' ) );
 	}
 
@@ -63,18 +60,19 @@
 	 *
 	 * @since 3.0.0
 	 */
-	function init() {
-		if ( ! current_user_can('edit_theme_options') )
+	public function init() {
+		$page = add_theme_page( __( 'Background' ), __( 'Background' ), 'edit_theme_options', 'custom-background', array( $this, 'admin_page' ) );
+		if ( ! $page ) {
 			return;
-
-		$this->page = $page = add_theme_page(__('Background'), __('Background'), 'edit_theme_options', 'custom-background', array($this, 'admin_page'));
+		}
 
-		add_action("load-$page", array($this, 'admin_load'));
-		add_action("load-$page", array($this, 'take_action'), 49);
-		add_action("load-$page", array($this, 'handle_upload'), 49);
+		add_action( "load-$page", array( $this, 'admin_load' ) );
+		add_action( "load-$page", array( $this, 'take_action' ), 49 );
+		add_action( "load-$page", array( $this, 'handle_upload' ), 49 );
 
-		if ( $this->admin_header_callback )
-			add_action("admin_head-$page", $this->admin_header_callback, 51);
+		if ( $this->admin_header_callback ) {
+			add_action( "admin_head-$page", $this->admin_header_callback, 51 );
+		}
 	}
 
 	/**
@@ -82,7 +80,7 @@
 	 *
 	 * @since 3.0.0
 	 */
-	function admin_load() {
+	public function admin_load() {
 		get_current_screen()->add_help_tab( array(
 			'id'      => 'overview',
 			'title'   => __('Overview'),
@@ -95,8 +93,8 @@
 
 		get_current_screen()->set_help_sidebar(
 			'<p><strong>' . __( 'For more information:' ) . '</strong></p>' .
-			'<p>' . __( '<a href="http://codex.wordpress.org/Appearance_Background_Screen" target="_blank">Documentation on Custom Background</a>' ) . '</p>' .
-			'<p>' . __( '<a href="http://wordpress.org/support/" target="_blank">Support Forums</a>' ) . '</p>'
+			'<p>' . __( '<a href="https://codex.wordpress.org/Appearance_Background_Screen" target="_blank">Documentation on Custom Background</a>' ) . '</p>' .
+			'<p>' . __( '<a href="https://wordpress.org/support/" target="_blank">Support Forums</a>' ) . '</p>'
 		);
 
 		wp_enqueue_media();
@@ -109,7 +107,7 @@
 	 *
 	 * @since 3.0.0
 	 */
-	function take_action() {
+	public function take_action() {
 
 		if ( empty($_POST) )
 			return;
@@ -176,54 +174,70 @@
 	 *
 	 * @since 3.0.0
 	 */
-	function admin_page() {
+	public function admin_page() {
 ?>
 <div class="wrap" id="custom-background">
-<?php screen_icon(); ?>
-<h2><?php _e('Custom Background'); ?></h2>
-<?php if ( !empty($this->updated) ) { ?>
+<h2><?php _e( 'Custom Background' ); ?></h2>
+
+<?php if ( current_user_can( 'customize' ) ) { ?>
+<div class="notice notice-info hide-if-no-customize">
+	<p>
+		<?php
+		printf(
+			__( 'You can now manage and live-preview Custom Backgrounds in the <a href="%1$s">Customizer</a>.' ),
+			admin_url( 'customize.php?autofocus[control]=background_image' )
+		);
+		?>
+	</p>
+</div>
+<?php } ?>
+
+<?php if ( ! empty( $this->updated ) ) { ?>
 <div id="message" class="updated">
 <p><?php printf( __( 'Background updated. <a href="%s">Visit your site</a> to see how it looks.' ), home_url( '/' ) ); ?></p>
 </div>
-<?php }
+<?php } ?>
 
-	if ( $this->admin_image_div_callback ) {
-		call_user_func($this->admin_image_div_callback);
-	} else {
-?>
-<h3><?php _e('Background Image'); ?></h3>
+<h3><?php _e( 'Background Image' ); ?></h3>
+
 <table class="form-table">
 <tbody>
-<tr valign="top">
-<th scope="row"><?php _e('Preview'); ?></th>
+<tr>
+<th scope="row"><?php _e( 'Preview' ); ?></th>
 <td>
-<?php
-$background_styles = '';
-if ( $bgcolor = get_background_color() )
-	$background_styles .= 'background-color: #' . $bgcolor . ';';
+	<?php
+	if ( $this->admin_image_div_callback ) {
+		call_user_func( $this->admin_image_div_callback );
+	} else {
+		$background_styles = '';
+		if ( $bgcolor = get_background_color() )
+			$background_styles .= 'background-color: #' . $bgcolor . ';';
 
-if ( get_background_image() ) {
-	$background_image_thumb = esc_url( set_url_scheme( get_theme_mod( 'background_image_thumb', str_replace( '%', '%%', get_background_image() ) ) ) );
-	// background-image URL must be single quote, see below
-	$background_styles .= ' background-image: url(\'' . $background_image_thumb . '\');'
-		. ' background-repeat: ' . get_theme_mod('background_repeat', 'repeat') . ';'
-		. ' background-position: top ' . get_theme_mod('background_position_x', 'left');
-}
-?>
-<div id="custom-background-image" style="<?php echo $background_styles; ?>"><?php // must be double quote, see above ?>
-<?php if ( get_background_image() ) { ?>
-<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" /><br />
-<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" />
-<?php } ?>
-</div>
-<?php } ?>
+		$background_image_thumb = get_background_image();
+		if ( $background_image_thumb ) {
+			$background_image_thumb = esc_url( set_url_scheme( get_theme_mod( 'background_image_thumb', str_replace( '%', '%%', $background_image_thumb ) ) ) );
+
+			// Background-image URL must be single quote, see below.
+			$background_styles .= ' background-image: url(\'' . $background_image_thumb . '\');'
+				. ' background-repeat: ' . get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) . ';'
+				. ' background-position: top ' . get_theme_mod( 'background_position_x', get_theme_support( 'custom-background', 'default-position-x' ) );
+		}
+	?>
+	<div id="custom-background-image" style="<?php echo $background_styles; ?>"><?php // must be double quote, see above ?>
+		<?php if ( $background_image_thumb ) { ?>
+		<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" /><br />
+		<img class="custom-background-image" src="<?php echo $background_image_thumb; ?>" style="visibility:hidden;" alt="" />
+		<?php } ?>
+	</div>
+	<?php } ?>
 </td>
 </tr>
+
 <?php if ( get_background_image() ) : ?>
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e('Remove Image'); ?></th>
 <td>
-<form method="post" action="">
+<form method="post">
 <?php wp_nonce_field('custom-background-remove', '_wpnonce-custom-background-remove'); ?>
 <?php submit_button( __( 'Remove Background Image' ), 'button', 'remove-background', false ); ?><br/>
 <?php _e('This will remove the background image. You will not be able to restore any customizations.') ?>
@@ -234,21 +248,21 @@
 
 <?php $default_image = get_theme_support( 'custom-background', 'default-image' ); ?>
 <?php if ( $default_image && get_background_image() != $default_image ) : ?>
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e('Restore Original Image'); ?></th>
 <td>
-<form method="post" action="">
+<form method="post">
 <?php wp_nonce_field('custom-background-reset', '_wpnonce-custom-background-reset'); ?>
 <?php submit_button( __( 'Restore Original Image' ), 'button', 'reset-background', false ); ?><br/>
 <?php _e('This will restore the original background image. You will not be able to restore any customizations.') ?>
 </form>
 </td>
 </tr>
+<?php endif; ?>
 
-<?php endif; ?>
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e('Select Image'); ?></th>
-<td><form enctype="multipart/form-data" id="upload-form" class="wp-upload-form" method="post" action="">
+<td><form enctype="multipart/form-data" id="upload-form" class="wp-upload-form" method="post">
 	<p>
 		<label for="upload"><?php _e( 'Choose an image from your computer:' ); ?></label><br />
 		<input type="file" id="upload" name="import" />
@@ -258,9 +272,9 @@
 	</p>
 	<p>
 		<label for="choose-from-library-link"><?php _e( 'Or choose an image from your media library:' ); ?></label><br />
-		<a id="choose-from-library-link" class="button"
+		<button id="choose-from-library-link" class="button"
 			data-choose="<?php esc_attr_e( 'Choose a Background Image' ); ?>"
-			data-update="<?php esc_attr_e( 'Set as background' ); ?>"><?php _e( 'Choose Image' ); ?></a>
+			data-update="<?php esc_attr_e( 'Set as background' ); ?>"><?php _e( 'Choose Image' ); ?></button>
 	</p>
 	</form>
 </td>
@@ -269,53 +283,53 @@
 </table>
 
 <h3><?php _e('Display Options') ?></h3>
-<form method="post" action="">
+<form method="post">
 <table class="form-table">
 <tbody>
 <?php if ( get_background_image() ) : ?>
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e( 'Position' ); ?></th>
 <td><fieldset><legend class="screen-reader-text"><span><?php _e( 'Background Position' ); ?></span></legend>
 <label>
-<input name="background-position-x" type="radio" value="left"<?php checked('left', get_theme_mod('background_position_x', 'left')); ?> />
+<input name="background-position-x" type="radio" value="left"<?php checked( 'left', get_theme_mod( 'background_position_x', get_theme_support( 'custom-background', 'default-position-x' ) ) ); ?> />
 <?php _e('Left') ?>
 </label>
 <label>
-<input name="background-position-x" type="radio" value="center"<?php checked('center', get_theme_mod('background_position_x', 'left')); ?> />
+<input name="background-position-x" type="radio" value="center"<?php checked( 'center', get_theme_mod( 'background_position_x', get_theme_support( 'custom-background', 'default-position-x' ) ) ); ?> />
 <?php _e('Center') ?>
 </label>
 <label>
-<input name="background-position-x" type="radio" value="right"<?php checked('right', get_theme_mod('background_position_x', 'left')); ?> />
+<input name="background-position-x" type="radio" value="right"<?php checked( 'right', get_theme_mod( 'background_position_x', get_theme_support( 'custom-background', 'default-position-x' ) ) ); ?> />
 <?php _e('Right') ?>
 </label>
 </fieldset></td>
 </tr>
 
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e( 'Repeat' ); ?></th>
 <td><fieldset><legend class="screen-reader-text"><span><?php _e( 'Background Repeat' ); ?></span></legend>
-<label><input type="radio" name="background-repeat" value="no-repeat"<?php checked('no-repeat', get_theme_mod('background_repeat', 'repeat')); ?> /> <?php _e('No Repeat'); ?></label>
-	<label><input type="radio" name="background-repeat" value="repeat"<?php checked('repeat', get_theme_mod('background_repeat', 'repeat')); ?> /> <?php _e('Tile'); ?></label>
-	<label><input type="radio" name="background-repeat" value="repeat-x"<?php checked('repeat-x', get_theme_mod('background_repeat', 'repeat')); ?> /> <?php _e('Tile Horizontally'); ?></label>
-	<label><input type="radio" name="background-repeat" value="repeat-y"<?php checked('repeat-y', get_theme_mod('background_repeat', 'repeat')); ?> /> <?php _e('Tile Vertically'); ?></label>
+<label><input type="radio" name="background-repeat" value="no-repeat"<?php checked( 'no-repeat', get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) ); ?> /> <?php _e('No Repeat'); ?></label>
+	<label><input type="radio" name="background-repeat" value="repeat"<?php checked( 'repeat', get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) ); ?> /> <?php _e('Tile'); ?></label>
+	<label><input type="radio" name="background-repeat" value="repeat-x"<?php checked( 'repeat-x', get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) ); ?> /> <?php _e('Tile Horizontally'); ?></label>
+	<label><input type="radio" name="background-repeat" value="repeat-y"<?php checked( 'repeat-y', get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) ) ); ?> /> <?php _e('Tile Vertically'); ?></label>
 </fieldset></td>
 </tr>
 
-<tr valign="top">
+<tr>
 <th scope="row"><?php _ex( 'Attachment', 'Background Attachment' ); ?></th>
 <td><fieldset><legend class="screen-reader-text"><span><?php _e( 'Background Attachment' ); ?></span></legend>
 <label>
-<input name="background-attachment" type="radio" value="scroll" <?php checked('scroll', get_theme_mod('background_attachment', 'scroll')); ?> />
-<?php _e('Scroll') ?>
+<input name="background-attachment" type="radio" value="scroll" <?php checked( 'scroll', get_theme_mod( 'background_attachment', get_theme_support( 'custom-background', 'default-attachment' ) ) ); ?> />
+<?php _e( 'Scroll' ); ?>
 </label>
 <label>
-<input name="background-attachment" type="radio" value="fixed" <?php checked('fixed', get_theme_mod('background_attachment', 'scroll')); ?> />
-<?php _e('Fixed') ?>
+<input name="background-attachment" type="radio" value="fixed" <?php checked( 'fixed', get_theme_mod( 'background_attachment', get_theme_support( 'custom-background', 'default-attachment' ) ) ); ?> />
+<?php _e( 'Fixed' ); ?>
 </label>
 </fieldset></td>
 </tr>
 <?php endif; // get_background_image() ?>
-<tr valign="top">
+<tr>
 <th scope="row"><?php _e( 'Background Color' ); ?></th>
 <td><fieldset><legend class="screen-reader-text"><span><?php _e( 'Background Color' ); ?></span></legend>
 <?php
@@ -342,7 +356,7 @@
 	 *
 	 * @since 3.0.0
 	 */
-	function handle_upload() {
+	public function handle_upload() {
 
 		if ( empty($_FILES) )
 			return;
@@ -351,7 +365,7 @@
 		$overrides = array('test_form' => false);
 
 		$uploaded_file = $_FILES['import'];
-		$wp_filetype = wp_check_filetype_and_ext( $uploaded_file['tmp_name'], $uploaded_file['name'], false );
+		$wp_filetype = wp_check_filetype_and_ext( $uploaded_file['tmp_name'], $uploaded_file['name'] );
 		if ( ! wp_match_mime_types( 'image', $wp_filetype['type'] ) )
 			wp_die( __( 'The uploaded file is not a valid image. Please try again.' ) );
 
@@ -392,23 +406,53 @@
 	}
 
 	/**
-	 * Unused since 3.5.0.
+	 * AJAX handler for adding custom background context to an attachment.
+	 *
+	 * Triggered when the user adds a new background image from the
+	 * Media Manager.
+	 *
+	 * @since 4.1.0
+	 */
+	public function ajax_background_add() {
+		check_ajax_referer( 'background-add', 'nonce' );
+
+		if ( ! current_user_can( 'edit_theme_options' ) ) {
+			wp_send_json_error();
+		}
+
+		$attachment_id = absint( $_POST['attachment_id'] );
+		if ( $attachment_id < 1 ) {
+			wp_send_json_error();
+		}
+
+		update_post_meta( $attachment_id, '_wp_attachment_is_custom_background', get_stylesheet() );
+
+		wp_send_json_success();
+	}
+
+	/**
 	 *
 	 * @since 3.4.0
+	 * @deprecated 3.5.0
 	 */
-	function attachment_fields_to_edit( $form_fields ) {
+	public function attachment_fields_to_edit( $form_fields ) {
 		return $form_fields;
 	}
 
 	/**
-	 * Unused since 3.5.0.
 	 *
 	 * @since 3.4.0
+	 * @deprecated 3.5.0
 	 */
-	function filter_upload_tabs( $tabs ) {
+	public function filter_upload_tabs( $tabs ) {
 		return $tabs;
 	}
 
+	/**
+	 *
+	 * @since 3.4.0
+	 * @deprecated 3.5.0
+	 */
 	public function wp_set_background_image() {
 		if ( ! current_user_can('edit_theme_options') || ! isset( $_POST['attachment_id'] ) ) exit;
 		$attachment_id = absint($_POST['attachment_id']);