Better indicate lack of variables in async call stacks

[dbaeumer]

microsoft/vscode#91326

When clicking through the call stack I noticed that for quite some frame no variables are shown. It is unclear to me whether this is a bug (I do think so since there are always variables in the frame) or whether the variables are not available anymore (in which case the debugger should tell me)

[connor4312]

It looks like you're in an async call stack--unfortunately Chrome only provides us variables for the current (synchronous) call stack. I will look into whether we can add any text to the variables view to indicate that state.

[connor4312]

Right now we don't have a good way to display errors/text in this case, see the linked issue. Once resolved I have a change ready to go that will show an appropriate message there.

[connor4312]

Added the error in js-debug, pending changes in vscode for it to actually be surfaced.

[rebornix]

@connor4312 what's the right js app to verify this issue? Or I can test this in any js app?

[connor4312]

Jackson verified this in microsoft/vscode#92102 (comment)