This CL reduces the complexity of the Subtractor.ConvergenceMultiChannel test by 1. Slightly reducing the amount of tested combinations for the non-debug mode. 2. Drastically reduce the amount of tested combinations for the debug mode. Bug: webrtc:11295 Change-Id: I56bfa4a1463d26e5217b6a4d7f2ef54de7aab512 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/166529 Commit-Queue: Per Åhgren <peah@webrtc.org> Reviewed-by: Sam Zackrisson <saza@webrtc.org> Cr-Commit-Position: refs/heads/master@{#30343}