Merge "libeffects: Testbench for Preprocessing effects agc, aec, ns" am: 8debb9f333 am: 98e41fa9c3 am: fa5e39ea56

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

Change-Id: I7feb454573751d3624351bebcf883211b0858b0f