Extend WebDriver to expose an AT Driver session id as a WebDriver capability

[zcorpan]

As discussed in yesterday's meeting, there should be a way to inform a WebDriver remote end when creating a WebDriver session that it should use an existing AT Driver session.

Consider a cloud-based service that supports both WebDriver and AT Driver. A user wants to test a particular screen reader and browser combination. Since the protocols are separate, the concepts of sessions are also separate. How would the service know to not create separate VMs for the two connections?

One way could be to specify an extension to WebDriver that allows the local end to send an AT Driver session id as a WebDriver capability.

[zcorpan]

Other options:

• Extend AT Driver to include WebDriver capabilities request
• Use an out-of-band protocol (e.g. an HTTP request/response) to request both AT Driver capabilities and WebDriver capabilities