Manually trigger change event. Why?

Unsure why this needs to be manually triggered, but its seems to.
2015-08-10 18:22:12 -04:00 · 2015-08-10 18:22:12 -04:00 · d8fdfe4c87
parent a8b1cabc0b
commit d8fdfe4c87
1 changed files with 1 additions and 0 deletions
--- a/assets/js/admin/settings-views-html-settings-tax.js
+++ b/assets/js/admin/settings-views-html-settings-tax.js
@ -24,6 +24,7 @@
 					if ( rates[ rateID ][ attribute ] !== value ) {
 						rates[ rateID ][ attribute ] = value;
 						this.set( 'rates', rates );
+						this.trigger( 'change:rates' ); // Why is this necessary?  Shouldn't the previous line trigger it?
 					}
 				}
 			} ),