Remove APM-internal usage of EchoControlMobile

This is a sibling CL to a similar one for EchoCancellation:
https://webrtc-review.googlesource.com/c/src/+/97603

 - EchoControlMobileImpl will no longer inherit EchoControlMobile.
 - Removes usage of AudioProcessing::echo_control_mobile() inside most of
   the audio processing module and unit tests.

The CL breaks audioproc_f backwards compatibility: It can no longer
use all recorded settings (comfort noise, routing mode), but prints an
error message when unsupported settings are encountered.

Tested: audioproc_f with .wav and aecdump inputs.
Bug: webrtc:9535
Change-Id: I63c3c81bcaf44021315978e1a0f3e42173b988ce
Reviewed-on: https://webrtc-review.googlesource.com/101621
Reviewed-by: Alex Loiko <aleloi@webrtc.org>
Commit-Queue: Sam Zackrisson <saza@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24888}
diff --git a/modules/audio_processing/audio_processing_impl.cc b/modules/audio_processing/audio_processing_impl.cc
index d5bb046..0772936 100644
--- a/modules/audio_processing/audio_processing_impl.cc
+++ b/modules/audio_processing/audio_processing_impl.cc
@@ -674,9 +674,8 @@
 
   public_submodules_->echo_cancellation->Enable(
       config_.echo_canceller.enabled && !config_.echo_canceller.mobile_mode);
-  static_cast<EchoControlMobile*>(public_submodules_->echo_control_mobile.get())
-      ->Enable(config_.echo_canceller.enabled &&
-               config_.echo_canceller.mobile_mode);
+  public_submodules_->echo_control_mobile->Enable(
+      config_.echo_canceller.enabled && config_.echo_canceller.mobile_mode);
 
   public_submodules_->echo_cancellation->set_suppression_level(
       config.echo_canceller.legacy_moderate_suppression_level