Specify frame destruction behavior

[marcoscaceres]

As a possible error condition, it would be good to spec out what happens when a navigable is destroyed that has request or is watching for a position.

Similarly to the frame no longer being fully active, it is possible to kick off a position request and then destroy the frame while holding a reference to the various callbacks or geolocation object.

We should check what user agents do in such cases, but it's probably best to specify in such cases they should avoid all watch/get operations and error with an abort error.

The spec should set up monitoring for the destruction of the script execution context, and trigger the abort behavior when the frame is destroyed.

[reillyeon]

Isn't this already covered by the end of the request a position algorithm when it checks whether the document is fully active?

[marcoscaceres]

Almost. This is if the focus becomes non-fully active because the frame (and its script execution context) was destroyed.

In such a case, we should abort and clean up/cancel any watch operations.