Improve error response message parsing for DAP evaluate requests.

[ashgti]

Updated the evaluate handler to check for DAP ErrorResponse bodies, which are used to display user errors if a request fails. This was updated in PR #167720

This should fix https://lab.llvm.org/buildbot/#/builders/163

[ashgti]

Also, cc @JDevlieghere I only recently realized there are 2 DAP implementations in llvm-project FYI.

[dyung]

Can we get this in soon? The cross project bots have been red ever since your original change landed.

[JDevlieghere]

Also, cc @JDevlieghere I only recently realized there are 2 DAP implementations in llvm-project FYI.

I knew Dexter was moving to DAP but I hadn't considered this implication. I think long term we should definitely try unify the two (potentially by hoisting parts into LLVM). @SLTozer do you agree?

[ashgti]

Merging to unblock ci but I do wonder if we should share parts of the Python client code so we don’t miss some things like this.

[SLTozer]

Merging to unblock ci but I do wonder if we should share parts of the Python client code so we don’t miss some things like this.

There could be benefits to having a shared implementation, but my gut says that it could also be more trouble than it's worth - although the debug adapter protocol is "generic", in practice it still seems to require some specialization per-debugger and per-client (from the small sample size I've observed), and I suspect the "Dexter version" might end up with significant deviations based on the needs of Dexter and the behaviour of other debug adapters. With that said, that's just my first impression - I'll take the time to compare the implementations in more detail later, since I agree it would simplify ongoing maintenance if the code could be shared.