Vue framework examples use wrong lifecycle hook to destroy foundation classes

[pgbross]

What MDC-Web Version are you using?

0.7.0

What browser(s) is this bug affecting?

Version 58.0.3029.19 beta (64-bit)

What OS are you using?

Fedora 25 (Linux p5q 4.9.13-201.fc25.x86_64)

What are the steps to reproduce the bug?

1. run the vue framework demo server
2. go to localhost:8080
3. set breakpoint on component's beforeUnmount (e.g. IconToggle.vue)
4. Cause component to be replaced (e.g. make a change to IconToggle.vue code such as add a console.log() message)
5. Observe the beforeUnmount() method is not called.

What is the expected behavior?

The correct lifecycle method is beforeDestroy(), see https://vuejs.org/v2/guide/instance.html#Lifecycle-Diagram

What is the actual behavior?

The underlying foundation class is never destroyed.

Any other information you believe would be useful?

The framework example is doesn't demonstrate the problem easily as none of the components used are normally destroyed by exercising the page. Adding a checkbox and using v-if directive to control the presence of a component, such as the icon-toggle, makes it simple to observe the correct beforeDestroy() method being called.