CreateNewUDCClientState is not safe to call more than once in a row

[bzbarsky-apple]

Problem

Consider the following order of events:

1. CreateNewUDCClientState is called.
2. Some time passes (e.g. thread lost timeslice)
3. CreateNewUDCClientState is called again and returns the same pointer because the time passed was enough for the state we got to not be considered initialized anymore.
4. Consumer now tries to do something with the state from step 1.

This never happens in our code right now (as long as all access to the UDC client states is on a single thread) because we never store the pointers CreateNewUDCClientState returns across another call to CreateNewUDCClientState. But this seems pretty fragile.

Proposed Solution

Figure out a safer API.

[chrisdecenzo]

Fixed in 8084, assigning to Boris to close

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[bzbarsky-apple]

And just to be clear, @chrisdecenzo this was not addressed in #8084

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.