UnobservedTaskExceptionEventArgs.SetObserved mentions old default

[dsherret]

For UnobservedTaskExceptionEventArgs.SetObserved() the remarks state:

The Exception property is used to examine the exception without marking it as observed, whereas the xref:System.Threading.Tasks.UnobservedTaskExceptionEventArgs.SetObserved%2A method is used to mark the exception as observed. Marking the exception as observed prevents it from triggering exception escalation policy which, by default, terminates the process.

But "by default" is no longer true. The default does not terminate the process since .net 4.5 because ThrowUnobservedTaskExceptions is now false by default.

[mairaw]

Thanks for your feedback @dsherret. @tarekgh, @stephentoub can you suggest how to approach this change?
This applies to the following page:
https://docs.microsoft.com/en-us/dotnet/api/system.threading.tasks.unobservedtaskexceptioneventargs

Since our docs cover all versions, we should state the old behavior and the new default behavior.

[stephentoub]

The post at https://devblogs.microsoft.com/pfxteam/task-exception-handling-in-net-4-5/ provides details on the change that was made for .NET 4.5. You could just clarify the "Marking the exception..." sentence that this is the case for either pre-.NET 4.5 or .NET 4.5+ if https://docs.microsoft.com/en-us/dotnet/framework/configure-apps/file-schema/runtime/throwunobservedtaskexceptions-element is set to true.

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Issue Details

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For UnobservedTaskExceptionEventArgs.SetObserved() the remarks state:

The Exception property is used to examine the exception without marking it as observed, whereas the xref:System.Threading.Tasks.UnobservedTaskExceptionEventArgs.SetObserved%2A method is used to mark the exception as observed. Marking the exception as observed prevents it from triggering exception escalation policy which, by default, terminates the process.

But "by default" is no longer true. The default does not terminate the process since .net 4.5 because ThrowUnobservedTaskExceptions is now false by default.

Author:	dsherret
Assignees:	-
Labels:	Pri2, waiting-on-feedback, doc-bug, Pri3, area-System.Threading.Tasks
Milestone:	Backlog