Taxes aren't being deducted when they should be

Problem/Motivation

When having VAT on products that is included in the price, the taxes aren't being deducted when shipping products abroad. When using the default commerce_price formatter, the VAT is being deducted correctly. This is an issue when using this formatter in the commerce_cart_form and commerce_checkout_order_summary views provided by commerce core.

The option Apply taxes to the calculated price doesn't affect the price. I did expect that to fix my problem, but it didn't.

I know, this is not what this module was intended for. But it'd be great if we could solve this.

Steps to reproduce

1. Enable Swiss VAT and set the prices entered to be including VAT.
2. Enable commerce_shipping
3. Create a default store with a Swiss Address
4. Set the price formatter in the cart form to use the formatter provided by this module
5. Create a product
6. Add it to the cart, proceed to checkout and enter any address outside Switzerland
7. Now the checkout summary correctly deducts the Swiss VAT from the price
8. The order form doesn't deduct the Swiss VAT

Proposed resolution

Deduct VAT the same way the commerce core price formatter does, if configured to do so. Maybe we need another option for this in the formatter?

Remaining tasks

User interface changes

API changes

Data model changes