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=600977
Committed: https://crrev.com/90a1351072a42f0b835f1c759f969ea014ce6b7f
Cr-Commit-Position: refs/heads/master@{#12318}

[danilchap, 2016-04-11 11:27:06]

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

[danilchap, 2016-04-11 11:27:07]

Same tests as in https://codereview.webrtc.org/1870573004/,
different approach to fix.

[åsapersson, 2016-04-11 15:36:02]

lgtm

[pbos-webrtc, 2016-04-11 16:10:01]

webrtc/test lgtm

[danilchap, 2016-04-11 16:46:18]

The CQ bit was checked by danilchap@webrtc.org

[commit-bot: I haz the power, 2016-04-11 16:46:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1880443002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1880443002/1

[commit-bot: I haz the power, 2016-04-11 17:05:05]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-11 17:05:13]

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=600977

Committed: https://crrev.com/90a1351072a42f0b835f1c759f969ea014ce6b7f
Cr-Commit-Position: refs/heads/master@{#12318}
==========

[commit-bot: I haz the power, 2016-04-11 17:05:14]

Patchset 1 (id:??) landed as
https://crrev.com/90a1351072a42f0b835f1c759f969ea014ce6b7f
Cr-Commit-Position: refs/heads/master@{#12318}