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- fuzzer corpus generator and fuzzer targets
- fftpack isolated as private test only target (only needed for the benchmark)

Bug: webrtc:9577
Change-Id: Idc904bc4b05f945a7461a14893518551bbe34b84
Reviewed-on: https://chromium-review.googlesource.com/c/1452000
Commit-Queue: Ale Bzk <alessiob@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Olga Sharonova <olka@chromium.org>
Reviewed-by: Max Moroz <mmoroz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629627}