Move session request feature before session creation

Author: Manishearth

index.bs

@@ -368,8 +368,6 @@ When this method is invoked, the user agent MUST run the following steps:
             1. [=Reject=] |promise| with a "{{NotSupportedError}}" {{DOMException}}.
             1. If |immersive| is <code>true</code>, set [=pending immersive session=] to <code>false</code>.
             1. Abort these steps.
-        1. Let |session| be a new {{XRSession}} object.
-        1. [=Initialize the session=] with |session|, |mode|, and |device|.
         1. Let |descriptor| be an {{XRPermissionDescriptor}} initialized with |mode|, |requiredFeatures|, and |optionalFeatures|
         1. Let |status| be an {{XRPermissionStatus}}, initially <code>null</code>
         1. [=Request the xr permission=] with |descriptor| and |status|.
@@ -384,6 +382,8 @@ When this method is invoked, the user agent MUST run the following steps:
               <dt> Otherwise
               <dd> Append |session| to the [=list of inline sessions=].
             </dl>
+        1. Let |session| be a new {{XRSession}} object.
+        1. [=Initialize the session=] with |session|, |mode|, and |device|.
         1. [=/Resolve=] |promise| with |session|.
         1. [=Queue a task=] to perform the following steps:
             NOTE: These steps ensure that initial <code>inputsourceschange</code> events occur after the initial session is resolved.