Adds fix for stream not updating when selected input device is null

[varunm0503]

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Pull Request Details

JIRA link(s):

Description

This PR resolves issue #256.
Issue is that audioHelper used to handle updating stream when 'default' device was selected as input device.

However, it is possible that selected input device is empty or null (initially). We should consider this scenario as well as if a default device has been selected. In this case as well, when we get a 'devicechange' event, we should refresh input stream.

Burndown

Before review

• Updated CHANGELOG.md if necessary
• Added unit tests if necessary
• Updated affected documentation
• Verified locally with npm test
• Manually sanity tested running locally
• Ready for review

Before merge

• Got one or more +1s
• Squashed erroneous commits if necessary
• Re-tested if necessary

[varunm0503]

Logs without fix: twilioWithoutFixLogs.txt

Logs with fix:
twilioLogsWithFixLogs.txt

Please go through the logs. Once you find "Disconnecting bluetooth" log, you can see that setInputDevice is never called after that without the fix applied. With the fix applied, you can find setInputDevice being called

[charliesantos]

Thanks for submitting @varunm0503 . We'll review and get back to you.

[charliesantos]

Thanks for your contribution @varunm0503 . I included this in a separate PR along with other fixes #270