title: Updating WooCommerce Subscriptions Order line Items programmatically
body: <p>I am trying to allow users to update line items of their subscriptions from their my account panel. I am able to get their subscription from subscription id and show them update form. Right now I show them with product items in their subscription that I got through </p>
  
  <pre><code>$subscription = wcs_get_subscription($_GET['subscription']);
  $subscription_items = $subscription-&gt;get_items();
  </code></pre>
  
  <p>What I am trying to do is allow users to update quantities of their product. So If they update quantity I want to update the subscription's item quantity so that future orders are generated with updated quantity. 
  I saw there is update_product method in <code>WC_Abstract_Order</code> class. I think this can be used but I am confused on this note in comments:</p>
  
  <pre><code>* Update a line item for the order.
  *
  * Note this does not update order totals.
  </code></pre>
  
  <p>Do I need to recalculate totals when I use this? 
  Also I needed to remove line item when quantity was 0. Is that possible? </p>
  
  <p>As I do not see a remove item method. </p>
  
  <p>Thanks</p>