Potential deadlock in TypeDescriptor

[steveharter]

Introduced by the recent PR #96846.

There are two sync objects being used (s_defaultProviderSyncObject, s_providerTable) and a deadlock is possible since the ordering of these 2 locks can vary and both locks rerequested.

The repro is to call TypeDescriptor.GetProvider(Type) and TypeDescriptor.AddProvider(..., Type) on different threads.

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Issue Details

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Introduced by #96846

[more details to come]

There are two sync objects being used (s_defaultProviderSyncObject, s_providerTable) and a deadlock looks like it is possible between these two in some rare cases. Working on repro using TypeDescriptor.GetProvider(Type) + `TypeDescriptor.AddProvider(..., Type) running on different threads.

Author:	steveharter
Assignees:	steveharter
Labels:	area-System.ComponentModel
Milestone:	9.0.0