Merge "libeffects: Testbench for Preprocessing effects agc, aec, ns" am: 8debb9f333 am: 98e41fa9c3

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/1366796

Change-Id: I60173142bebafa57730d4b3f8029dacf4e61525e