Add backtraces to errors

[jedel1043]

As part of our focus on improving our Error APIs, we need to introduce backtraces to errors generated at execution. This includes:

• Adding a Backtrace struct.
• Retrofitting our VM to hold the current backtrace.
• Adding names to all native functions.
• Storing the current backtrace inside every thrown JsError.

[raskad]

Do you think it makes sense to consider TCO when we implement this? We could make sure both work together or decide that we do not want to implement TCO.

See the discussion in #3510.

[jedel1043]

Yep. Though, I think a well designed backtrace API would isolate both issues e.g. errors would get a stacktrace without knowing the internals of whether the VM has a "shadow trace" or not.