Editor: Use Event#preventDefault for shortcuts unbinding

packages/editor/src/components/rich-text/remove-browser-shortcuts.js

@@ -1,18 +1,45 @@
+/**
+ * External dependencies
+ */
+import { fromPairs } from 'lodash';
+
 /**
  * WordPress dependencies
  */
 import { rawShortcut } from '@wordpress/keycodes';
 import { KeyboardShortcuts } from '@wordpress/components';
 
-export function RemoveBrowserShortcuts() {
-	return (
-		<KeyboardShortcuts
-			bindGlobal
-			shortcuts={ {
-				[ rawShortcut.primary( 'z' ) ]: () => false,
-				[ rawShortcut.primaryShift( 'z' ) ]: () => false,
-				[ rawShortcut.primary( 'y' ) ]: () => false,
-			} }
-		/>
-	);
-}
+/**
+ * Set of keyboard shortcuts handled internally by RichText.
+ *
+ * @type {Array}
+ */
+const HANDLED_SHORTCUTS = [
+	rawShortcut.primary( 'z' ),
+	rawShortcut.primaryShift( 'z' ),
+	rawShortcut.primary( 'y' ),
+];
+
+/**
+ * An instance of a KeyboardShortcuts element pre-bound for the handled
+ * shortcuts. Since shortcuts never change, the element can be considered
+ * static, and can be skipped in reconciliation.
+ *
+ * @type {WPElement}
+ */
+const SHORTCUTS_ELEMENT = (
+	<KeyboardShortcuts
+		bindGlobal
+		shortcuts={ fromPairs( HANDLED_SHORTCUTS.map( ( shortcut ) => {
+			return [ shortcut, ( event ) => event.preventDefault() ];
+		} ) ) }
+	/>
+);
+
+/**
+ * Component which registered keyboard event handlers to prevent default
+ * behaviors for key combinations otherwise handled internally by RichText.
+ *
+ * @return {WPElement} WordPress element.
+ */
+export const RemoveBrowserShortcuts = () => SHORTCUTS_ELEMENT;