Send credentials on logout (#13)

Send credentials on logout

Author: smalinin

src/RelyingParty.js

@@ -397,13 +397,17 @@ class RelyingParty extends JSONDocument {
       return Promise.reject(error)
     }
 
-    this.clearSession()
+    if (!configuration.end_session_endpoint) {
+      this.clearSession()
+      return Promise.resolve(undefined)
+    }
 
     let uri = configuration.end_session_endpoint
     let method = 'get'
 
-    return fetch(uri, {method})
+    return fetch(uri, {method, credentials: 'include'})
       .then(onHttpError('Error logging out'))
+      .then(() => this.clearSession())
 
     // TODO: Validate `frontchannel_logout_uri` if necessary
     /**