chore(ckeditor5-footnotes): integrate source code changes

packages/ckeditor5-footnotes/src/constants.ts

@@ -0,0 +1,35 @@
+export const TOOLBAR_COMPONENT_NAME = 'footnote';
+export const DATA_FOOTNOTE_ID = 'data-footnote-id';
+
+export const ELEMENTS = {
+	footnoteItem: 'footnoteItem',
+	footnoteReference: 'footnoteReference',
+	footnoteSection: 'footnoteSection',
+	footnoteContent: 'footnoteContent',
+	footnoteBackLink: 'footnoteBackLink'
+};
+
+export const CLASSES = {
+	footnoteContent: 'footnote-content',
+	footnoteItem: 'footnote-item',
+	footnoteReference: 'footnote-reference',
+	footnoteSection: 'footnote-section',
+	footnoteBackLink: 'footnote-back-link',
+	footnotes: 'footnotes', // a class already used on our sites for the footnote section
+	hidden: 'hidden'
+};
+
+export const COMMANDS = {
+	insertFootnote: 'InsertFootnote'
+};
+
+export const ATTRIBUTES = {
+	footnoteContent: 'data-footnote-content',
+	footnoteId: 'data-footnote-id',
+	footnoteIndex: 'data-footnote-index',
+	footnoteItem: 'data-footnote-item',
+	footnoteReference: 'data-footnote-reference',
+	footnoteSection: 'data-footnote-section',
+	footnoteBackLink: 'data-footnote-back-link',
+	footnoteBackLinkHref: 'data-footnote-back-link-href'
+};