Updates bonanza

wp-includes/theme.php

@@ -110,9 +110,11 @@ function wp_get_theme( $stylesheet = null, $theme_root = null ) {
  * Clears the cache held by get_theme_roots() and WP_Theme.
  *
  * @since 3.5.0
+ * @param bool $clear_update_cache Whether to clear the Theme updates cache
  */
-function wp_clean_themes_cache() {
-	delete_site_transient('update_themes');
+function wp_clean_themes_cache( $clear_update_cache = true ) {
+	if ( $clear_update_cache )
+		delete_site_transient( 'update_themes' );
 	search_theme_directories( true );
 	foreach ( wp_get_themes( array( 'errors' => null ) ) as $theme )
 		$theme->cache_delete();
@@ -139,19 +141,24 @@ function is_child_theme() {
  * going to be the same for most cases.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'stylesheet' filter on stylesheet name.
  *
  * @return string Stylesheet name.
  */
 function get_stylesheet() {
-	return apply_filters('stylesheet', get_option('stylesheet'));
+	/**
+	 * Filter the name of current stylesheet.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $stylesheet Name of the current stylesheet.
+	 */
+	return apply_filters( 'stylesheet', get_option( 'stylesheet' ) );
 }
 
 /**
  * Retrieve stylesheet directory path for current theme.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'stylesheet_directory' filter on stylesheet directory and theme name.
  *
  * @return string Path to current theme directory.
  */
@@ -160,6 +167,15 @@ function get_stylesheet_directory() {
 	$theme_root = get_theme_root( $stylesheet );
 	$stylesheet_dir = "$theme_root/$stylesheet";
 
+	/**
+	 * Filter the stylesheet directory path for current theme.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $stylesheet_dir Absolute path to the current them.
+	 * @param string $stylesheet     Directory name of the current theme.
+	 * @param string $theme_root     Absolute path to themes directory.
+	 */
 	return apply_filters( 'stylesheet_directory', $stylesheet_dir, $stylesheet, $theme_root );
 }
 
@@ -171,10 +187,19 @@ function get_stylesheet_directory() {
  * @return string
  */
 function get_stylesheet_directory_uri() {
-	$stylesheet = get_stylesheet();
+	$stylesheet = str_replace( '%2F', '/', rawurlencode( get_stylesheet() ) );
 	$theme_root_uri = get_theme_root_uri( $stylesheet );
 	$stylesheet_dir_uri = "$theme_root_uri/$stylesheet";
 
+	/**
+	 * Filter the stylesheet directory URI.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $stylesheet_dir_uri Stylesheet directory URI.
+	 * @param string $stylesheet         Name of the activated theme's directory.
+	 * @param string $theme_root_uri     Themes root URI.
+	 */
 	return apply_filters( 'stylesheet_directory_uri', $stylesheet_dir_uri, $stylesheet, $theme_root_uri );
 }
 
@@ -185,14 +210,21 @@ function get_stylesheet_directory_uri() {
  * get_stylesheet_directory_uri() stylesheet directory URI} path.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'stylesheet_uri' filter on stylesheet URI path and stylesheet directory URI.
  *
  * @return string
  */
 function get_stylesheet_uri() {
 	$stylesheet_dir_uri = get_stylesheet_directory_uri();
 	$stylesheet_uri = $stylesheet_dir_uri . '/style.css';
-	return apply_filters('stylesheet_uri', $stylesheet_uri, $stylesheet_dir_uri);
+	/**
+	 * Filter the URI of the current theme stylesheet.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $stylesheet_uri     Stylesheet URI for the current theme/child theme.
+	 * @param string $stylesheet_dir_uri Stylesheet directory URI for the current theme/child theme.
+	 */
+	return apply_filters( 'stylesheet_uri', $stylesheet_uri, $stylesheet_dir_uri );
 }
 
 /**
@@ -210,7 +242,6 @@ function get_stylesheet_uri() {
  * separate folder, then change the latter.
  *
  * @since 2.1.0
- * @uses apply_filters() Calls 'locale_stylesheet_uri' filter on stylesheet URI path and stylesheet directory URI.
  *
  * @return string
  */
@@ -225,7 +256,15 @@ function get_locale_stylesheet_uri() {
 		$stylesheet_uri = "$stylesheet_dir_uri/{$wp_locale->text_direction}.css";
 	else
 		$stylesheet_uri = '';
-	return apply_filters('locale_stylesheet_uri', $stylesheet_uri, $stylesheet_dir_uri);
+	/**
+	 * Filter the localized stylesheet URI.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param string $stylesheet_uri     Localized stylesheet URI.
+	 * @param string $stylesheet_dir_uri Stylesheet directory URI.
+	 */
+	return apply_filters( 'locale_stylesheet_uri', $stylesheet_uri, $stylesheet_dir_uri );
 }
 
 /**
@@ -237,14 +276,20 @@ function get_locale_stylesheet_uri() {
  * @return string Template name.
  */
 function get_template() {
-	return apply_filters('template', get_option('template'));
+	/**
+	 * Filter the name of the current theme.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $template Current theme's directory name.
+	 */
+	return apply_filters( 'template', get_option( 'template' ) );
 }
 
 /**
  * Retrieve current theme directory.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'template_directory' filter on template directory path and template name.
  *
  * @return string Template directory path.
  */
@@ -253,6 +298,15 @@ function get_template_directory() {
 	$theme_root = get_theme_root( $template );
 	$template_dir = "$theme_root/$template";
 
+	/**
+	 * Filter the current theme directory path.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $template_dir The URI of the current theme directory.
+	 * @param string $template     Directory name of the current theme.
+	 * @param string $theme_root   Absolute path to the themes directory.
+	 */
 	return apply_filters( 'template_directory', $template_dir, $template, $theme_root );
 }
 
@@ -260,15 +314,23 @@ function get_template_directory() {
  * Retrieve theme directory URI.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'template_directory_uri' filter on template directory URI path and template name.
  *
  * @return string Template directory URI.
  */
 function get_template_directory_uri() {
-	$template = get_template();
+	$template = str_replace( '%2F', '/', rawurlencode( get_template() ) );
 	$theme_root_uri = get_theme_root_uri( $template );
 	$template_dir_uri = "$theme_root_uri/$template";
 
+	/**
+	 * Filter the current theme directory URI.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $template_dir_uri The URI of the current theme directory.
+	 * @param string $template         Directory name of the current theme.
+	 * @param string $theme_root_uri   The themes root URI.
+	 */
 	return apply_filters( 'template_directory_uri', $template_dir_uri, $template, $theme_root_uri );
 }
 
@@ -340,7 +402,7 @@ function search_theme_directories( $force = false ) {
 
 	// Set up maybe-relative, maybe-absolute array of theme directories.
 	// We always want to return absolute, but we need to cache relative
-	// use in for get_theme_root().
+	// to use in get_theme_root().
 	foreach ( $wp_theme_directories as $theme_root ) {
 		if ( 0 === strpos( $theme_root, WP_CONTENT_DIR ) )
 			$relative_theme_roots[ str_replace( WP_CONTENT_DIR, '', $theme_root ) ] = $theme_root;
@@ -348,6 +410,14 @@ function search_theme_directories( $force = false ) {
 			$relative_theme_roots[ $theme_root ] = $theme_root;
 	}
 
+	/**
+	 * Filter whether to get the cache of the registered theme directories.
+	 *
+	 * @since 3.4.0
+	 *
+	 * @param bool   $cache_expiration Whether to get the cache of the theme directories. Default false.
+	 * @param string $cache_directory  Directory to be searched for the cache.
+	 */
 	if ( $cache_expiration = apply_filters( 'wp_cache_themes_persistently', false, 'search_theme_directories' ) ) {
 		$cached_roots = get_site_transient( 'theme_roots' );
 		if ( is_array( $cached_roots ) ) {
@@ -373,8 +443,10 @@ function search_theme_directories( $force = false ) {
 
 		// Start with directories in the root of the current theme directory.
 		$dirs = @ scandir( $theme_root );
-		if ( ! $dirs )
-			return false;
+		if ( ! $dirs ) {
+			trigger_error( "$theme_root is not readable", E_USER_NOTICE );
+			continue;
+		}
 		foreach ( $dirs as $dir ) {
 			if ( ! is_dir( $theme_root . '/' . $dir ) || $dir[0] == '.' || $dir == 'CVS' )
 				continue;
@@ -390,8 +462,10 @@ function search_theme_directories( $force = false ) {
 				// wp-content/themes/a-folder-of-themes/*
 				// wp-content/themes is $theme_root, a-folder-of-themes is $dir, then themes are $sub_dirs
 				$sub_dirs = @ scandir( $theme_root . '/' . $dir );
-				if ( ! $sub_dirs )
-					return false;
+				if ( ! $sub_dirs ) {
+					trigger_error( "$theme_root/$dir is not readable", E_USER_NOTICE );
+					continue;
+				}
 				foreach ( $sub_dirs as $sub_dir ) {
 					if ( ! is_dir( $theme_root . '/' . $dir . '/' . $sub_dir ) || $dir[0] == '.' || $dir == 'CVS' )
 						continue;
@@ -435,7 +509,6 @@ function search_theme_directories( $force = false ) {
  * Does not have trailing slash.
  *
  * @since 1.5.0
- * @uses apply_filters() Calls 'theme_root' filter on path.
  *
  * @param string $stylesheet_or_template The stylesheet or template name of the theme
  * @return string Theme path.
@@ -452,6 +525,13 @@ function get_theme_root( $stylesheet_or_template = false ) {
 		$theme_root = WP_CONTENT_DIR . '/themes';
 	}
 
+	/**
+	 * Filter the absolute path to the themes directory.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $theme_root Absolute path to themes directory.
+	 */
 	return apply_filters( 'theme_root', $theme_root );
 }
 
@@ -492,7 +572,16 @@ function get_theme_root_uri( $stylesheet_or_template = false, $theme_root = fals
 		$theme_root_uri = content_url( 'themes' );
 	}
 
-	return apply_filters( 'theme_root_uri', $theme_root_uri, get_option('siteurl'), $stylesheet_or_template );
+	/**
+	 * Filter the URI for themes directory.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string $theme_root_uri         The URI for themes directory.
+	 * @param string $siteurl                WordPress web address which is set in General Options.
+	 * @param string $stylesheet_or_template Stylesheet or template name of the theme.
+	 */
+	return apply_filters( 'theme_root_uri', $theme_root_uri, get_option( 'siteurl' ), $stylesheet_or_template );
 }
 
 /**
@@ -544,7 +633,7 @@ function locale_stylesheet() {
 /**
  * Start preview theme output buffer.
  *
- * Will only preform task if the user has permissions and template and preview
+ * Will only perform task if the user has permissions and template and preview
  * query variables exist.
  *
  * @since 2.6.0
@@ -631,7 +720,7 @@ function preview_theme_ob_filter( $content ) {
  */
 function preview_theme_ob_filter_callback( $matches ) {
 	if ( strpos($matches[4], 'onclick') !== false )
-		$matches[4] = preg_replace('#onclick=([\'"]).*?(?<!\\\)\\1#i', '', $matches[4]); //Strip out any onclicks from rest of <a>. (?<!\\\) means to ignore the '" if its escaped by \  to prevent breaking mid-attribute.
+		$matches[4] = preg_replace('#onclick=([\'"]).*?(?<!\\\)\\1#i', '', $matches[4]); //Strip out any onclicks from rest of <a>. (?<!\\\) means to ignore the '" if it's escaped by \  to prevent breaking mid-attribute.
 	if (
 		( false !== strpos($matches[3], '/wp-admin/') )
 	||
@@ -643,7 +732,10 @@ function preview_theme_ob_filter_callback( $matches ) {
 	)
 		return $matches[1] . "#$matches[2] onclick=$matches[2]return false;" . $matches[4];
 
-	$link = add_query_arg( array( 'preview' => 1, 'template' => $_GET['template'], 'stylesheet' => @$_GET['stylesheet'], 'preview_iframe' => 1 ), $matches[3] );
+	$stylesheet = isset( $_GET['stylesheet'] ) ? $_GET['stylesheet'] : '';
+	$template   = isset( $_GET['template'] )   ? $_GET['template']   : '';
+
+	$link = add_query_arg( array( 'preview' => 1, 'template' => $template, 'stylesheet' => $stylesheet, 'preview_iframe' => 1 ), $matches[3] );
 	if ( 0 === strpos($link, 'preview=1') )
 		$link = "?$link";
 	return $matches[1] . esc_attr( $link ) . $matches[4];
@@ -656,15 +748,22 @@ function preview_theme_ob_filter_callback( $matches ) {
  * of two arguments: $template then $stylesheet. This is for backwards compatibility.
  *
  * @since 2.5.0
- * @uses do_action() Calls 'switch_theme' action, passing the new theme.
  *
  * @param string $stylesheet Stylesheet name
  */
 function switch_theme( $stylesheet ) {
-	global $wp_theme_directories, $sidebars_widgets;
+	global $wp_theme_directories, $wp_customize, $sidebars_widgets;
 
-	if ( is_array( $sidebars_widgets ) )
-		set_theme_mod( 'sidebars_widgets', array( 'time' => time(), 'data' => $sidebars_widgets ) );
+	$_sidebars_widgets = null;
+	if ( 'wp_ajax_customize_save' === current_action() ) {
+		$_sidebars_widgets = $wp_customize->post_value( $wp_customize->get_setting( 'old_sidebars_widgets_data' ) );
+	} elseif ( is_array( $sidebars_widgets ) ) {
+		$_sidebars_widgets = $sidebars_widgets;
+	}
+
+	if ( is_array( $_sidebars_widgets ) ) {
+		set_theme_mod( 'sidebars_widgets', array( 'time' => time(), 'data' => $_sidebars_widgets ) );
+	}
 
 	$old_theme  = wp_get_theme();
 	$new_theme = wp_get_theme( $stylesheet );
@@ -691,12 +790,30 @@ function switch_theme( $stylesheet ) {
 
 	update_option( 'current_theme', $new_name );
 
+	// Migrate from the old mods_{name} option to theme_mods_{slug}.
 	if ( is_admin() && false === get_option( 'theme_mods_' . $stylesheet ) ) {
 		$default_theme_mods = (array) get_option( 'mods_' . $new_name );
 		add_option( "theme_mods_$stylesheet", $default_theme_mods );
+	} else {
+		/*
+		 * Since retrieve_widgets() is called when initializing the customizer theme,
+		 * we need to to remove the theme mods to avoid overwriting changes made via
+		 * the widget customizer when accessing wp-admin/widgets.php.
+		 */
+		if ( 'wp_ajax_customize_save' === current_action() ) {
+			remove_theme_mod( 'sidebars_widgets' );
+		}
 	}
 
 	update_option( 'theme_switched', $old_theme->get_stylesheet() );
+	/**
+	 * Fires after the theme is switched.
+	 *
+	 * @since 1.5.0
+	 *
+	 * @param string   $new_name  Name of the new theme.
+	 * @param WP_Theme $new_theme WP_Theme instance of the new theme.
+	 */
 	do_action( 'switch_theme', $new_name, $new_theme );
 }
 
@@ -714,8 +831,14 @@ function switch_theme( $stylesheet ) {
  * @return bool
  */
 function validate_current_theme() {
-	// Don't validate during an install/upgrade.
-	if ( defined('WP_INSTALLING') || !apply_filters( 'validate_current_theme', true ) )
+	/**
+	 * Filter whether to validate the current theme.
+	 *
+	 * @since 2.7.0
+	 *
+	 * @param bool true Validation flag to check the current theme.
+	 */
+	if ( defined('WP_INSTALLING') || ! apply_filters( 'validate_current_theme', true ) )
 		return true;
 
 	if ( get_template() != WP_DEFAULT_THEME && !file_exists(get_template_directory() . '/index.php') ) {
@@ -767,7 +890,6 @@ function get_theme_mods() {
  * directory URI.
  *
  * @since 2.1.0
- * @uses apply_filters() Calls 'theme_mod_$name' filter on the value.
  *
  * @param string $name Theme modification name.
  * @param bool|string $default
@@ -776,13 +898,27 @@ function get_theme_mods() {
 function get_theme_mod( $name, $default = false ) {
 	$mods = get_theme_mods();
 
-	if ( isset( $mods[ $name ] ) )
-		return apply_filters( "theme_mod_$name", $mods[ $name ] );
+	if ( isset( $mods[$name] ) ) {
+		/**
+		 * Filter the theme modification, or 'theme_mod', value.
+		 *
+		 * The dynamic portion of the hook name, $name, refers to
+		 * the key name of the modification array. For example,
+		 * 'header_textcolor', 'header_image', and so on depending
+		 * on the theme options.
+		 *
+		 * @since 2.2.0
+		 *
+		 * @param string $current_mod The value of the current theme modification.
+		 */
+		return apply_filters( "theme_mod_{$name}", $mods[$name] );
+	}
 
 	if ( is_string( $default ) )
 		$default = sprintf( $default, get_template_directory_uri(), get_stylesheet_directory_uri() );
 
-	return apply_filters( "theme_mod_$name", $default );
+	/** This filter is documented in wp-includes/theme.php */
+	return apply_filters( "theme_mod_{$name}", $default );
 }
 
 /**
@@ -795,8 +931,21 @@ function get_theme_mod( $name, $default = false ) {
  */
 function set_theme_mod( $name, $value ) {
 	$mods = get_theme_mods();
+	$old_value = isset( $mods[ $name ] ) ? $mods[ $name ] : false;
 
-	$mods[ $name ] = $value;
+	/**
+	 * Filter the theme mod value on save.
+	 *
+	 * The dynamic portion of the hook name, $name, refers to the key name of
+	 * the modification array. For example, 'header_textcolor', 'header_image',
+	 * and so on depending on the theme options.
+	 *
+	 * @since 3.9.0
+	 *
+	 * @param string $value     The new value of the theme mod.
+	 * @param string $old_value The current value of the theme mod.
+	 */
+	$mods[ $name ] = apply_filters( "pre_set_theme_mod_$name", $value, $old_value );
 
 	$theme = get_option( 'stylesheet' );
 	update_option( "theme_mods_$theme", $mods );
@@ -981,12 +1130,12 @@ function is_random_header_image( $type = 'any' ) {
 }
 
 /**
- * Display header image path.
+ * Display header image URL.
  *
  * @since 2.1.0
  */
 function header_image() {
-	echo get_header_image();
+	echo esc_url( get_header_image() );
 }
 
 /**
@@ -1006,15 +1155,17 @@ function get_uploaded_header_images() {
 		return array();
 
 	foreach ( (array) $headers as $header ) {
-		$url = esc_url_raw( $header->guid );
+		$url = esc_url_raw( wp_get_attachment_url( $header->ID ) );
 		$header_data = wp_get_attachment_metadata( $header->ID );
 		$header_index = basename($url);
 		$header_images[$header_index] = array();
 		$header_images[$header_index]['attachment_id'] =  $header->ID;
 		$header_images[$header_index]['url'] =  $url;
 		$header_images[$header_index]['thumbnail_url'] =  $url;
-		$header_images[$header_index]['width'] = $header_data['width'];
-		$header_images[$header_index]['height'] = $header_data['height'];
+		if ( isset( $header_data['width'] ) )
+			$header_images[$header_index]['width'] = $header_data['width'];
+		if ( isset( $header_data['height'] ) )
+			$header_images[$header_index]['height'] = $header_data['height'];
 	}
 
 	return $header_images;
@@ -1084,7 +1235,8 @@ function register_default_headers( $headers ) {
  * @since 3.0.0
  *
  * @param string|array $header The header string id (key of array) to remove, or an array thereof.
- * @return True on success, false on failure.
+ * @return bool|void A single header returns true on success, false on failure.
+ *                   There is currently no return value for multiple headers.
  */
 function unregister_default_headers( $header ) {
 	global $_wp_default_headers;
@@ -1150,7 +1302,11 @@ function _custom_background_cb() {
 
 	// $color is the saved custom color.
 	// A default has to be specified in style.css. It will not be printed here.
-	$color = get_theme_mod( 'background_color' );
+	$color = get_background_color();
+
+	if ( $color === get_theme_support( 'custom-background', 'default-color' ) ) {
+		$color = false;
+	}
 
 	if ( ! $background && ! $color )
 		return;
@@ -1160,17 +1316,17 @@ function _custom_background_cb() {
 	if ( $background ) {
 		$image = " background-image: url('$background');";
 
-		$repeat = get_theme_mod( 'background_repeat', 'repeat' );
+		$repeat = get_theme_mod( 'background_repeat', get_theme_support( 'custom-background', 'default-repeat' ) );
 		if ( ! in_array( $repeat, array( 'no-repeat', 'repeat-x', 'repeat-y', 'repeat' ) ) )
 			$repeat = 'repeat';
 		$repeat = " background-repeat: $repeat;";
 
-		$position = get_theme_mod( 'background_position_x', 'left' );
+		$position = get_theme_mod( 'background_position_x', get_theme_support( 'custom-background', 'default-position-x' ) );
 		if ( ! in_array( $position, array( 'center', 'right', 'left' ) ) )
 			$position = 'left';
 		$position = " background-position: top $position;";
 
-		$attachment = get_theme_mod( 'background_attachment', 'scroll' );
+		$attachment = get_theme_mod( 'background_attachment', get_theme_support( 'custom-background', 'default-attachment' ) );
 		if ( ! in_array( $attachment, array( 'fixed', 'scroll' ) ) )
 			$attachment = 'scroll';
 		$attachment = " background-attachment: $attachment;";
@@ -1246,7 +1402,9 @@ function remove_editor_styles() {
  * The init hook may be too late for some features.
  *
  * @since 2.9.0
- * @param string $feature the feature being added
+ *
+ * @param string $feature The feature being added.
+ * @return void|bool False on failure, void otherwise.
  */
 function add_theme_support( $feature ) {
 	global $_wp_theme_features;
@@ -1262,6 +1420,21 @@ function add_theme_support( $feature ) {
 				$args[0] = array_intersect( $args[0], array_keys( get_post_format_slugs() ) );
 			break;
 
+		case 'html5' :
+			// You can't just pass 'html5', you need to pass an array of types.
+			if ( empty( $args[0] ) ) {
+				// Build an array of types for back-compat.
+				$args = array( 0 => array( 'comment-list', 'comment-form', 'search-form' ) );
+			} elseif ( ! is_array( $args[0] ) ) {
+				_doing_it_wrong( "add_theme_support( 'html5' )", 'You need to pass an array of types.', '3.6.1' );
+				return false;
+			}
+
+			// Calling 'html5' again merges, rather than overwrites.
+			if ( isset( $_wp_theme_features['html5'] ) )
+				$args[0] = array_merge( $_wp_theme_features['html5'][0], $args[0] );
+			break;
+
 		case 'custom-header-uploads' :
 			return add_theme_support( 'custom-header', array( 'uploads' => true ) );
 			break;
@@ -1348,10 +1521,13 @@ function add_theme_support( $feature ) {
 				$args = array( 0 => array() );
 
 			$defaults = array(
-				'default-image' => '',
-				'default-color' => '',
-				'wp-head-callback' => '_custom_background_cb',
-				'admin-head-callback' => '',
+				'default-image'          => '',
+				'default-repeat'         => 'repeat',
+				'default-position-x'     => 'left',
+				'default-attachment'     => 'scroll',
+				'default-color'          => '',
+				'wp-head-callback'       => '_custom_background_cb',
+				'admin-head-callback'    => '',
 				'admin-preview-callback' => '',
 			);
 
@@ -1422,7 +1598,8 @@ add_action( 'wp_loaded', '_custom_header_background_just_in_time' );
 /**
  * Gets the theme support arguments passed when registering that support
  *
- * @since 3.1
+ * @since 3.1.0
+ *
  * @param string $feature the feature to check
  * @return array The array of extra arguments
  */
@@ -1489,7 +1666,7 @@ function _remove_theme_support( $feature ) {
 
 	switch ( $feature ) {
 		case 'custom-header' :
-			if ( false === did_action( 'wp_loaded', '_custom_header_background_just_in_time' ) )
+			if ( ! did_action( 'wp_loaded' ) )
 				break;
 			$support = get_theme_support( 'custom-header' );
 			if ( $support[0]['wp-head-callback'] )
@@ -1499,7 +1676,7 @@ function _remove_theme_support( $feature ) {
 			break;
 
 		case 'custom-background' :
-			if ( false === did_action( 'wp_loaded', '_custom_header_background_just_in_time' ) )
+			if ( ! did_action( 'wp_loaded' ) )
 				break;
 			$support = get_theme_support( 'custom-background' );
 			remove_action( 'wp_head', $support[0]['wp-head-callback'] );
@@ -1545,11 +1722,15 @@ function current_theme_supports( $feature ) {
 			return in_array( $content_type, $_wp_theme_features[$feature][0] );
 			break;
 
+		case 'html5':
 		case 'post-formats':
 			// specific post formats can be registered by passing an array of types to
 			// add_theme_support()
-			$post_format = $args[0];
-			return in_array( $post_format, $_wp_theme_features[$feature][0] );
+
+			// Specific areas of HTML5 support *must* be passed via an array to add_theme_support()
+
+			$type = $args[0];
+			return in_array( $type, $_wp_theme_features[$feature][0] );
 			break;
 
 		case 'custom-header':
@@ -1561,19 +1742,38 @@ function current_theme_supports( $feature ) {
 			break;
 	}
 
-	return apply_filters('current_theme_supports-' . $feature, true, $args, $_wp_theme_features[$feature]);
+	/**
+	 * Filter whether the current theme supports a specific feature.
+	 *
+	 * The dynamic portion of the hook name, $feature, refers to
+	 * the specific theme feature. Possible values include 'post-formats',
+	 * 'post-thumbnails', 'custom-background', 'custom-header', 'menus',
+	 * 'automatic-feed-links', and 'html5'.
+	 *
+	 * @since 3.4.0
+	 *
+	 * @param bool   true     Whether the current theme supports the given feature. Default true.
+	 * @param array  $args    Array of arguments for the feature.
+	 * @param string $feature The theme feature.
+	 */
+	return apply_filters( "current_theme_supports-{$feature}", true, $args, $_wp_theme_features[$feature] );
 }
 
 /**
  * Checks a theme's support for a given feature before loading the functions which implement it.
  *
  * @since 2.9.0
- * @param string $feature the feature being checked
- * @param string $include the file containing the functions that implement the feature
+ *
+ * @param string $feature The feature being checked.
+ * @param string $include Path to the file.
+ * @return bool True if the current theme supports the supplied feature, false otherwise.
  */
-function require_if_theme_supports( $feature, $include) {
-	if ( current_theme_supports( $feature ) )
+function require_if_theme_supports( $feature, $include ) {
+	if ( current_theme_supports( $feature ) ) {
 		require ( $include );
+		return true;
+	}
+	return false;
 }
 
 /**
@@ -1609,10 +1809,31 @@ function check_theme_switched() {
 	if ( $stylesheet = get_option( 'theme_switched' ) ) {
 		$old_theme = wp_get_theme( $stylesheet );
 
-		if ( $old_theme->exists() )
-			do_action( 'after_switch_theme', $old_theme->get('Name'), $old_theme );
-		else
+		// Prevent retrieve_widgets() from running since Customizer already called it up front
+		if ( get_option( 'theme_switched_via_customizer' ) ) {
+			remove_action( 'after_switch_theme', '_wp_sidebars_changed' );
+			update_option( 'theme_switched_via_customizer', false );
+		}
+
+		if ( $old_theme->exists() ) {
+			/**
+			 * Fires on the first WP load after a theme switch if the old theme still exists.
+			 *
+			 * This action fires multiple times and the parameters differs
+			 * according to the context, if the old theme exists or not.
+			 * If the old theme is missing, the parameter will be the slug
+			 * of the old theme.
+			 *
+			 * @since 3.3.0
+			 *
+			 * @param string   $old_name  Old theme name.
+			 * @param WP_Theme $old_theme WP_Theme instance of the old theme.
+			 */
+			do_action( 'after_switch_theme', $old_theme->get( 'Name' ), $old_theme );
+		} else {
+			/** This action is documented in wp-includes/theme.php */
 			do_action( 'after_switch_theme', $stylesheet );
+		}
 
 		update_option( 'theme_switched', false );
 	}
@@ -1721,4 +1942,4 @@ function wp_customize_support_script() {
 		}());
 	</script>
 	<?php
-}
+}