Update Stripe PHP API

Summary: Ref T2787. This brings us up to date.

Test Plan: `git clone`

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T2787

Differential Revision: https://secure.phabricator.com/D9916

externals/stripe-php/lib/Stripe/Subscription.php

@@ -0,0 +1,57 @@
+<?php
+
+class Stripe_Subscription extends Stripe_ApiResource
+{
+  /**
+   * @return string The API URL for this Stripe subscription.
+   */
+  public function instanceUrl()
+  {
+    $id = $this['id'];
+    $customer = $this['customer'];
+    if (!$id) {
+      throw new Stripe_InvalidRequestError(
+          "Could not determine which URL to request: " .
+          "class instance has invalid ID: $id",
+          null
+      );
+    }
+    $id = Stripe_ApiRequestor::utf8($id);
+    $customer = Stripe_ApiRequestor::utf8($customer);
+
+    $base = self::classUrl('Stripe_Customer');
+    $customerExtn = urlencode($customer);
+    $extn = urlencode($id);
+    return "$base/$customerExtn/subscriptions/$extn";
+  }
+
+  /**
+   * @param array|null $params
+   * @return Stripe_Subscription The deleted subscription.
+   */
+  public function cancel($params=null)
+  {
+    $class = get_class();
+    return self::_scopedDelete($class, $params);
+  }
+
+  /**
+   * @return Stripe_Subscription The saved subscription.
+   */
+  public function save()
+  {
+    $class = get_class();
+    return self::_scopedSave($class);
+  }
+
+  /**
+   * @return Stripe_Subscription The updated subscription.
+   */
+  public function deleteDiscount()
+  {
+    $requestor = new Stripe_ApiRequestor($this->_apiKey);
+    $url = $this->instanceUrl() . '/discount';
+    list($response, $apiKey) = $requestor->request('delete', $url);
+    $this->refreshFrom(array('discount' => null), $apiKey, true);
+  }
+}