Errors inside the SDK are not reported to the callback

In debugging #962, I found that the error was not passed back to the callback, which prevents proper debugging in deployment. In addition to logging the error, the error should have been passed to the callback.

Start with the debugging case described in #962 and trace the SDK operation that logs errors and invokes its callback. Confirm how errors are currently handled at that entry point, then verify that the callback receives the error as well as the error being logged.

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