Revert "[TIZEN] Tag the audio stream as "browser" in pulseaudio."

These changes are not needed anymore since the Murphy integration
is in place and we are setting media role for streams while creating
Murphy resource.

This reverts commit 731fb7f83c8535399647e8a9630ea842ecbd4321.
Merge pull request #191 from nagineni/pulseaudio

Revert "[TIZEN] Tag the audio stream as "browser" in pulseaudio."