Remove options remapping, use settings directly.

[tomalec]

⚠️ This PR requires #328

Changes proposed in this Pull Request:

• Remove options remapping, use settings directly.
  Fix ga_ecommerce_tracking_enabled is not sent to tracker data #359

I don't see any value in having another layer that's just a copy of the existing ->settings. Having three places to store the same thing may lead to more bugs like #359, where the objects get out of sync.

• Remove redundant WC_Google_Analytics properties
  use $this->settings directly.
  All the properties, except ga_id, were not used at all. ga_id was used only once.

Checks:

• Does your code follow the WordPress coding standards?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Screenshots:

Detailed test instructions:

1. Go to WooCommerce > Settings > Integration > Google Analytics wp-admin/admin.php?page=wc-settings&tab=integration&section=google_analytics
2. Make sure " Purchase Transactions" is checked
3. Check the value of all the settings match the tracker data

   wp wc tracker snapshot --format=json | jq '.[0]["wc-google-analytics"]' 
   

4. Check that wcgaiData.config matches the settings
5. Smoke test the plugin

Additional details:

1. I think we can consider one more tweak: removing the static get function and using the settings array directly. A static function that relies on the property set by the instance constructor looks bug-prone. Plus, defining a function to do $this->get( 'foo' ) instead of $this->settings['foo'], makes the code less explicit and does not bring much value IMO

Changelog entry

Dev - Remove options remapping, use settings directly.

[martynmjones]

Hey @tomalec, thanks for tidying up the extension settings 🙌

Tracking is working as expected and the correct events are being loaded into the wcgaiData object so LGTM ✅