am f43ac911: Merge "Handle OPTIONS requests from SIP servers." into gingerbread

Merge commit 'f43ac911379c15b6a1a240a931b0f3cbfb2fae53' into gingerbread-plus-aosp

* commit 'f43ac911379c15b6a1a240a931b0f3cbfb2fae53':
  Handle OPTIONS requests from SIP servers.