Customizer: Improve handling of crops in the media library.

This is a follow up on r41732, implementing the following improvements:

* Attachment parent info is now stored in attachment meta rather than a 
separate post meta key.
* Attachments created from contextual crops (e.g. header, logos, etc.) are
filtered out of the media library using a new `_filterContext` method in
`wp.media.controller.Library`.

Props joemcgill, westonruter.
See #21819.

Built from https://develop.svn.wordpress.org/trunk@41937


git-svn-id: http://core.svn.wordpress.org/trunk@41771 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/custom-header.php

@@ -1187,6 +1187,11 @@ wp_nonce_field( 'custom-header-options', '_wpnonce-custom-header-options' ); ?>
 		$attachment_id = wp_insert_attachment( $object, $cropped );
 		$metadata = wp_generate_attachment_metadata( $attachment_id, $cropped );
 
+		// If this is a crop, save the original attachment ID as metadata.
+		if ( $parent_id ) {
+			$metadata['attachment_parent'] = $parent_id;
+		}
+
 		/**
 		 * Filters the header image attachment metadata.
 		 *
@@ -1197,11 +1202,8 @@ wp_nonce_field( 'custom-header-options', '_wpnonce-custom-header-options' ); ?>
 		 * @param array $metadata Attachment metadata.
 		 */
 		$metadata = apply_filters( 'wp_header_image_attachment_metadata', $metadata );
-		wp_update_attachment_metadata( $attachment_id, $metadata );
 
-		if ( $parent_id ) {
-			$meta = add_post_meta( $attachment_id, '_wp_attachment_parent', $parent_id, true );
-		}
+		wp_update_attachment_metadata( $attachment_id, $metadata );
 
 		return $attachment_id;
 	}

wp-includes/js/media-views.js

@@ -953,6 +953,9 @@ Library = wp.media.controller.State.extend(/** @lends wp.media.controller.Librar
 			}) );
 		}
 
+		this._filterContext();
+		this.get('library').on( 'add', this._filterContext, this );
+
 		this.resetDisplays();
 	},
 
@@ -1152,6 +1155,19 @@ Library = wp.media.controller.State.extend(/** @lends wp.media.controller.Librar
 		if ( view && view.get( mode ) ) {
 			setUserSetting( 'libraryContent', mode );
 		}
+	},
+
+	/**
+	 * Filter out contextually created attachments (e.g. headers, logos, etc.)
+	 *
+	 * @since 4.9.0
+	 */
+	_filterContext: function() {
+		var library = this.get('library');
+
+		library.set( library.filter( function( item ) {
+			return item.get('context') === '';
+		} ) );
 	}
 });
 

wp-includes/media.php

@@ -3159,6 +3159,9 @@ function wp_prepare_attachment_for_js( $attachment ) {
 		$response['filesizeHumanReadable'] = size_format( $bytes );
 	}
 
+	$context = get_post_meta( $attachment->ID, '_wp_attachment_context', true );
+	$response['context'] = ( $context ) ? $context : '';
+
 	if ( current_user_can( 'edit_post', $attachment->ID ) ) {
 		$response['nonces']['update'] = wp_create_nonce( 'update-post_' . $attachment->ID );
 		$response['nonces']['edit'] = wp_create_nonce( 'image_editor-' . $attachment->ID );

wp-includes/theme.php

@@ -1214,7 +1214,7 @@ function get_uploaded_header_images() {
 		$header_images[$header_index]['url'] =  $url;
 		$header_images[$header_index]['thumbnail_url'] = $url;
 		$header_images[$header_index]['alt_text'] = get_post_meta( $header->ID, '_wp_attachment_image_alt', true );
-		$header_images[$header_index]['attachment_parent'] = (int) get_post_meta( $header->ID, '_wp_attachment_parent', true );
+		$header_images[$header_index]['attachment_parent'] = isset( $header_data['attachment_parent'] ) ? $header_data['attachment_parent'] : '';
 
 		if ( isset( $header_data['width'] ) )
 			$header_images[$header_index]['width'] = $header_data['width'];

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-beta2-41936';
+$wp_version = '4.9-beta2-41937';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.