Fixed rtcp rpsi parsing of invalid packets.

Fixed rtcp rpsi parsing of invalid packets.
Added packet type RpsiItem to destinguish parsed rpsi header and Rpsi body
  preventing handling two half-valid (header-only) rpsi packets as one valid,
  making test parser calculate rpsi packet once instead of twice.
Added check padding bits doesn't exceed native bit string length.
Marking rpsi received moved after it is validated.

BUG=chromium:600977
R=asapersson@webrtc.org, pbos@webrtc.org

Committed: https://chromium.googlesource.com/external/webrtc/+/c7bb9e52402c1eeeadee0264c5c6b4a2e6fdb31d

[danilchap, 2016-04-29 08:15:42]

Description was changed from

==========
Fixed rtcp rpsi parsing of invalid packets. Added packet type RpsiItem to
destinguish parsed rpsi header and Rpsi body   preventing handling two
half-valid (header-only) rpsi packets as one valid,   making test parser
calculate rpsi packet once instead of twice. Added check padding bits doesn't
exceed native bit string length. Marking rpsi received moved after it is
validated.

BUG=600977
==========

to

==========
Fixed rtcp rpsi parsing of invalid packets.
Added packet type RpsiItem to destinguish parsed rpsi header and Rpsi body
  preventing handling two half-valid (header-only) rpsi packets as one valid,
  making test parser calculate rpsi packet once instead of twice.
Added check padding bits doesn't exceed native bit string length.
Marking rpsi received moved after it is validated.

BUG=chromium:600977
==========

[danilchap, 2016-04-29 08:15:42]

danilchap@webrtc.org changed reviewers:
+ asapersson@webrtc.org, pbos@webrtc.org

[danilchap, 2016-04-29 08:17:09]

This is merge of the https://codereview.webrtc.org/1880443002/ into M51

[pbos-webrtc, 2016-05-02 00:17:15]

lgtm

[åsapersson, 2016-05-02 10:18:46]

lgtm

[danilchap, 2016-05-02 10:29:07]

Description was changed from

==========
Fixed rtcp rpsi parsing of invalid packets.
Added packet type RpsiItem to destinguish parsed rpsi header and Rpsi body
  preventing handling two half-valid (header-only) rpsi packets as one valid,
  making test parser calculate rpsi packet once instead of twice.
Added check padding bits doesn't exceed native bit string length.
Marking rpsi received moved after it is validated.

BUG=chromium:600977
==========

to

==========
Fixed rtcp rpsi parsing of invalid packets.
Added packet type RpsiItem to destinguish parsed rpsi header and Rpsi body
  preventing handling two half-valid (header-only) rpsi packets as one valid,
  making test parser calculate rpsi packet once instead of twice.
Added check padding bits doesn't exceed native bit string length.
Marking rpsi received moved after it is validated.

BUG=chromium:600977
R=asapersson@webrtc.org, pbos@webrtc.org

Committed:
https://chromium.googlesource.com/external/webrtc/+/c7bb9e52402c1eeeadee0264c...
==========

[danilchap, 2016-05-02 10:29:08]

Committed patchset #1 (id:1) manually as
c7bb9e52402c1eeeadee0264c5c6b4a2e6fdb31d (presubmit successful).