Record a tracks event when merchant toggles cart shipping calculator: (https://github.com/woocommerce/woocommerce-blocks/pull/1975)

* record a tracks event when merchant toggles cart shipping calculator:
- add tracks utility func for blocks
  - adds standard event name prefix
  - supplies post id & type params (an example)
- hook this up to UI when user toggles shipping calc
- pass enabled as boolean prop

* fix typo - call isTracksAvailable() !

* remove unnecessary temporary boolean

* update event name based on best practice guidelines

* remove isTracksAvailable preflight check:
- if site opts out, recordEvent is an empty function
- add in standard fallback boilerplate to ensure function exists
Note: currently no mechanism to detect if tracks is available on front end.

plugins/woocommerce-blocks/assets/js/base/utils/index.js

@@ -1,3 +1,4 @@
 export * from './errors';
 export * from './price';
 export * from './address';
+export * from './tracks';

plugins/woocommerce-blocks/assets/js/base/utils/tracks.js

@@ -0,0 +1,23 @@
+/**
+ * External dependencies
+ */
+import { select } from '@wordpress/data';
+
+// Stand-in wcTracks.recordEvent in case tracks is not available (for any reason).
+window.wcTracks = window.wcTracks || {};
+window.wcTracks.recordEvent = window.wcTracks.recordEvent || function() {};
+
+export const recordEditorEvent = function( event, props ) {
+	// Force prefix - our editor events will be 'wcadmin_blocks_*'.
+	const blocksPrefix = 'blocks_';
+
+	const postData = select( 'core/editor' );
+
+	// If tracks is not available (e.g. opt-out), recordEvent is a no-op.
+	window.wcTracks.recordEvent( blocksPrefix + event, {
+		// Automatically include post id and post type props.
+		post_id: postData.getCurrentPostId(),
+		post_type: postData.getCurrentPostType(),
+		...props,
+	} );
+};

plugins/woocommerce-blocks/assets/js/blocks/cart-checkout/cart/edit.js

@@ -19,6 +19,7 @@ import { EditorProvider, useEditorContext } from '@woocommerce/base-context';
 import { useSelect } from '@wordpress/data';
 import { __experimentalCreateInterpolateElement } from 'wordpress-element';
 import { getAdminLink } from '@woocommerce/settings';
+import { recordEditorEvent } from '@woocommerce/base-utils';
 
 /**
  * Internal dependencies
@@ -85,11 +86,17 @@ const BlockSettings = ( { attributes, setAttributes } ) => {
 						'woo-gutenberg-products-block'
 					) }
 					checked={ isShippingCalculatorEnabled }
-					onChange={ () =>
+					onChange={ () => {
+						recordEditorEvent(
+							'cart_settings_shipping_calculator_toggle',
+							{
+								enabled: ! isShippingCalculatorEnabled,
+							}
+						);
 						setAttributes( {
 							isShippingCalculatorEnabled: ! isShippingCalculatorEnabled,
-						} )
+						} );
-					}
+					} }
 				/>
 				<ToggleControl
 					label={ __(