Created Issue: Unhandled exception in debugger [776]

Manually killing the debugee process while debugging can cause VS to crash.

```
---------------------------
Assertion Failed: Abort=Quit, Retry=Debug, Ignore=Continue
---------------------------
An unhandled exception is about to terminate the process. Exception info:
System.IO.IOException: Debugger connection was closed.

at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)

at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)

at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()

at Microsoft.NodejsTools.Debugger.Communication.DebuggerClient.<SendRequestAsync>d__2.MoveNext()

--- End of stack trace from previous location where exception was thrown ---

at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)

at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)

at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()

at Microsoft.NodejsTools.Debugger.NodeDebugger.<ContinueAsync>d__11.MoveNext()

--- End of stack trace from previous location where exception was thrown ---

at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)

at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)

at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()

at Microsoft.NodejsTools.Debugger.NodeDebugger.<ReportException>d__69.MoveNext()

--- End of stack trace from previous location where exception was thrown ---

at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>b__5(Object state)

at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state)

at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)

at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)

at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()

at System.Threading.ThreadPoolWorkQueue.Dispatch()

at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()



at Microsoft.VisualStudioTools.Project.UIThread.<Initialize>b__9(Object sender, UnhandledExceptionEventArgs args)

at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>b__5(Object state)

at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state)

at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)

at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)

at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()

at System.Threading.ThreadPoolWorkQueue.Dispatch()

at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()


---------------------------
Abort Retry Ignore
---------------------------
```