Remove deprecated legacy AEC code

This CL removes the deprecated legacy AEC code.

Note that this CL should not be landed before the M80 release has been cut.

Bug: webrtc:11165
Change-Id: I59ee94526e62f702bb9fa9fa2d38c4e48f44753c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/161238
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30036}
diff --git a/modules/audio_processing/include/config.h b/modules/audio_processing/include/config.h
index 930cf7e..8a24586 100644
--- a/modules/audio_processing/include/config.h
+++ b/modules/audio_processing/include/config.h
@@ -27,15 +27,15 @@
   kNetEqCapacityConfig,    // Deprecated
   kNetEqFastAccelerate,    // Deprecated
   kVoicePacing,            // Deprecated
-  kExtendedFilter,
-  kDelayAgnostic,
+  kExtendedFilter,         // Deprecated
+  kDelayAgnostic,          // Deprecated
   kExperimentalAgc,
   kExperimentalNs,
-  kBeamforming,      // Deprecated
-  kIntelligibility,  // Deprecated
-  kEchoCanceller3,   // Deprecated
-  kAecRefinedAdaptiveFilter,
-  kLevelControl  // Deprecated
+  kBeamforming,               // Deprecated
+  kIntelligibility,           // Deprecated
+  kEchoCanceller3,            // Deprecated
+  kAecRefinedAdaptiveFilter,  // Deprecated
+  kLevelControl               // Deprecated
 };
 
 // Class Config is designed to ease passing a set of options across webrtc code.