am fb861523: Merge "Specification of codec specific data as part of the session description is now optional." into gingerbread

Merge commit 'fb861523318710b95c08110b9b2de28f7da74a40' into gingerbread-plus-aosp

* commit 'fb861523318710b95c08110b9b2de28f7da74a40':
  Specification of codec specific data as part of the session description is now optional.