Block warning: add convert to classic option

Makes use of the new ellipsis menu to present the sa,e convert to blocks option along with a convert to classic block

packages/editor/src/components/block-list/block-invalid-warning.js

@@ -15,7 +15,7 @@ import { withDispatch } from '@wordpress/data';
  */
 import Warning from '../warning';
 
-function BlockInvalidWarning( { convertToHTML, convertToBlocks } ) {
+function BlockInvalidWarning( { convertToHTML, convertToBlocks, convertToClassic } ) {
 	const hasHTMLBlock = !! getBlockType( 'core/html' );
 
 	return (
@@ -30,6 +30,10 @@ function BlockInvalidWarning( { convertToHTML, convertToBlocks } ) {
 					</Button>
 				),
 			] }
+			hiddenActions={ [
+				{ title: __( 'Convert to Blocks' ), onClick: convertToBlocks },
+				{ title: __( 'Convert to Classic Block' ), onClick: convertToClassic },
+			] }
 		>
 			{ __( 'This block has been modified externally.' ) }
 		</Warning>
@@ -39,6 +43,11 @@ function BlockInvalidWarning( { convertToHTML, convertToBlocks } ) {
 export default withDispatch( ( dispatch, { block } ) => {
 	const { replaceBlock } = dispatch( 'core/editor' );
 	return {
+		convertToClassic() {
+			replaceBlock( block.uid, createBlock( 'core/freeform', {
+				content: block.originalContent,
+			} ) );
+		},
 		convertToHTML() {
 			replaceBlock( block.clientId, createBlock( 'core/html', {
 				content: block.originalContent,