Audio Context warning about using it without a user gesture

[sbates-idrc]

"The AudioContext was not allowed to start. It must be resumed (or created) after a user gesture on the page. https://goo.gl/7K7WLu"

Currently appearing in 4 places:

• audio-context-constructor.ts:40
• test-audio-node-disconnect-method-support.ts:45
• test-audio-scheduled-source-node-start-method-negative-parameters-support.ts:7
• constant-source-node-constructor.ts:85

Comment Simon 2020-11-30:

We have tried a number of strategies for delaying the initialization and playing of sounds in Tone.js, but we haven't been able to get rid of the warnings.

There is a Tone.js issue with some discussion regarding "The AudioContext was not allowed to start" warnings: Tonejs/Tone.js#776. And at this point, it looks most likely that the warnings are from Tone.js code that is out of our control.

I'm going to leave this issue open, but we won't do any more work on it for now. If Tone.js is changed to remove these warnings, at that time we can see if we need to make any code changes.

Original Jira issue: https://fluidproject.atlassian.net/browse/C2LC-253