Accelerator allowlisting

Experimental library and tools for determining whether an accelerator engine works well on a given device, and for a given model.

Platform-agnostic, Android-first

Android-focused, since the much smaller set of configurations on iOS means there is much less need for allowlisting on iOS.

Not just for TfLite

This code lives in the TfLite codebase, since TfLite is the first open-source customer. It is however meant to support other users (direct use of NNAPI, mediapipe).