Send analytics data when onboarding dismissed

services/web/public/coffee/ide/AutoCompileOnboardingController.coffee

@@ -22,4 +22,5 @@ define [
 			})
 
 		$scope.dismiss = () ->
-			$scope.onboarding.autoCompile = 'dismissed'
+			$scope.onboarding.autoCompile = 'dismissed'
+			event_tracking.sendMB "shown-autocompile-onboarding"