Add 'processEvent' to debug protocol

[gregg-miskelly]

This defines a new 'processEvent' to resolve #122

[msftclas]

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[gregg-miskelly]

FYI @andrewcrawley @DavidKarlas @weinand

[andrewcrawley]

LGTM. When would isLocalProcess be false? Every "remote" scenario I'm aware of has the machine boundary between the UI and the debug adapter, not between the DA and the debuggee.

[gregg-miskelly]

@andrewcrawley -- I would expect that debug adapters that are remoted themselves should probably not set this at all (unless they are aware of when they are being remoted). The one place I was expecting to use this was in vsdbg-ui since it is always local and could give the IDE which is talking to it information about if the process was local or not.

[DavidKarlas]

LGTM

[weinand]

FYI: Debug adapters cannot run remote because the DAP uses local file paths, so there is an assumption that they run side by side with the frontend/client and they have access to the workspace.
It would be possible to remove this assumption (by changing the DAP), but this would be a breaking change.

[weinand]

@gregg-miskelly Perfect! Thanks for the PR.