Only close inserter on Escape or button press on inserter toggle

Remove the useDialog hook, as it was only used for focus outside and escape keypresses to close the inserter. It doesn't appear any semantics were added. This manually implements an escape keypress hook to close the inserter when focus is inside the inserter.

packages/editor/src/components/inserter-sidebar/index.js

@@ -5,13 +5,11 @@ import { useDispatch, useSelect } from '@wordpress/data';
 import { Button, VisuallyHidden } from '@wordpress/components';
 import { __experimentalLibrary as Library } from '@wordpress/block-editor';
 import { close } from '@wordpress/icons';
-import {
-	useViewportMatch,
-	__experimentalUseDialog as useDialog,
-} from '@wordpress/compose';
+import { useViewportMatch, useRefEffect } from '@wordpress/compose';
 import { __ } from '@wordpress/i18n';
 import { useEffect, useRef } from '@wordpress/element';
 import { store as preferencesStore } from '@wordpress/preferences';
+import { ESCAPE } from '@wordpress/keycodes';
 
 /**
  * Internal dependencies
@@ -35,22 +33,34 @@ export default function InserterSidebar( {
 
 	const isMobileViewport = useViewportMatch( 'medium', '<' );
 	const TagName = ! isMobileViewport ? VisuallyHidden : 'div';
-	const [ inserterDialogRef, inserterDialogProps ] = useDialog( {
-		onClose: () => setIsInserterOpened( false ),
-		focusOnMount: null,
-	} );
 
 	const libraryRef = useRef();
 	useEffect( () => {
 		libraryRef.current.focusSearch();
 	}, [] );
 
+	const useEscape = useRefEffect( ( element ) => {
+		function onKeyDown( event ) {
+			const { keyCode } = event;
+
+			if ( event.defaultPrevented ) {
+				return;
+			}
+
+			if ( keyCode === ESCAPE ) {
+				event.preventDefault();
+				setIsInserterOpened( false );
+			}
+		}
+
+		element.addEventListener( 'keydown', onKeyDown );
+		return () => {
+			element.removeEventListener( 'keydown', onKeyDown );
+		};
+	}, [] );
+
 	return (
-		<div
-			ref={ inserterDialogRef }
-			{ ...inserterDialogProps }
-			className="editor-inserter-sidebar"
-		>
+		<div ref={ useEscape } className="editor-inserter-sidebar">
 			<TagName className="editor-inserter-sidebar__header">
 				<Button
 					icon={ close }