Add padding support to Packetizer

[alexpokotilo]

To add padding-only samples call GeneratePadding

Description

Sometime for Bandwidth estimation purposes we need to add Padding-only packages to the stream before switching to new rendition. Once this branch merges I will add pull request to add necessary support to TrackLocalStaticSample in webrtc repo.

[Sean-Der]

@alexpokotilo LGTM! What do you think of different name like CreatePadding or GeneratePadding.

I didn't understand the purpose of the function until I read the code.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 27 lines in your changes are missing coverage. Please review.

Project coverage is 86.41%. Comparing base (7dc2af5) to head (1f351cb).
Report is 7 commits behind head on master.

Files	Patch %	Lines
packetizer.go	0.00%	27 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #251      +/-   ##
==========================================
- Coverage   87.50%   86.41%   -1.10%     
==========================================
  Files          20       21       +1     
  Lines        1873     2156     +283     
==========================================
+ Hits         1639     1863     +224     
- Misses        204      257      +53     
- Partials       30       36       +6     

Flag	Coverage Δ
go	86.41% <0.00%> (-1.10%)	⬇️
wasm	85.89% <0.00%> (-1.02%)	⬇️

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[alexpokotilo]

@alexpokotilo LGTM! What do you think of different name like CreatePadding or GeneratePadding.

I didn't understand the purpose of the function until I read the code.

Sean,
thanks for your feedback.
I've changed to GeneratePadding.

[Sean-Der]

Merged! Thank you so much @alexpokotilo

Can I add you to the Pion org? You can create branches and will run tests for you. Would love to work closer together!

[alexpokotilo]

Merged! Thank you so much @alexpokotilo

Can I add you to the Pion org? You can create branches and will run tests for you. Would love to work closer together!

@Sean-Der
It's a great honor to be part of Pion org! You can definitely add me.

[alexpokotilo]

@Sean-Der,
as I've said I have some delta in webrtc repository https://github.com/alexpokotilo/webrtc/tree/static-sample-padding-support to support padding in TrackLocalStaticSample. To pull merge request I need:

1. new rtp version with tag 1.8.5 releases. It looks like this will be done automatically. But I don't know how to trigger this.
2. pion/master and pion/v3 upgraded rtp version to 1.8.5.
   I'll file two merge requests for pion/master and for pion/v3.
   I can upgrade go.mod for pion/v3 and pion/master myself in my pull requests. Or there is another process to do this ?

Should I just wait till new rtp tag 1.8.5 released automatically or I need to do something ?

[Sean-Der]

You are never bothering me! I really appreciate you being involved :) I am sorry I am so slow to respond!

Ping me in the Pion Slack that is much lower volume and I will respond instantly. Email/GitHub is hard for me because I get so much it is hard to filter