Port webkitAudioContext code to standards based AudioContext for Virtual Hang
Revert "Port webkitAudioContext code to standards based AudioContext for Virtual Hang"

This reverts commit f5e4c90cac88d36554cd129339969a8f94945251.
Virtual Hang Branch Version 1.2

Port webkitAudioContext code to standards based AudioContext for Virtual
Hang Version 1.2