1. Use $already_reduced_stock instead of also considering $refunded_item_quantity while deleting orders. This will bring back part of #27504 again, but for now this seems to be the best solution for countering #28605. It needs discussion whether deleting a line item completely should also undo any refund related changes on it or not.
2. Also mark `stock_reduced` flag on order if any of the line item has any `_reduced_stock` flag. This will allow for stock restoring logic to work properly when order is cancelled.
3. Only adjust line item stock when order is in `processing`, `completed` or `on-hold` status state, because we need to reduce stocks on these status only. Stock adjustments in refunds or when changing statuses is already taken care of by their specific hooks.
This commit adds again the Travis function `travis_retry` (https://docs.travis-ci.com/user/common-build-problems/#travis_retry) to all the commands used to execute the E2E tests as they sometimes fail due to factors outside our control and they pass if we retry them manually. See for example this issue for an instance where often times the E2E tests fail, the issue describes a problem that happened in a local environment, but we see the same error happening on Travis as well: https://github.com/woocommerce/woocommerce/issues/27846. I actually just saw it and had to restart a Travis build job manually and that is what prompted me to create this commit. Having Travis retry the command automatically should save us some time when we review PRs as there is a chance the command will pass on a subsequent run and we won't have to retry it manually and wait for it to finish.
We have used this function in the past (see 67b5b270f3), but it got removed in 1658dd3962. But after some conversation about it a couple of weeks ago, we decided to use it again.
This commit adds the 'Select a country / region...' text as a placeholder text displayed in the country select field indicating to the user that they need to select a country. This is only needed when the option ¨Default customer location" is set to "No location by default".