Remove the useless ACMTest base class

Bug: webrtc:8396
Change-Id: I021a2429910b21ffe4829e0ed51b9290bc715c0c
Reviewed-on: https://webrtc-review.googlesource.com/102884
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24907}
diff --git a/modules/audio_coding/test/TestAllCodecs.h b/modules/audio_coding/test/TestAllCodecs.h
index 03539ff..669a118 100644
--- a/modules/audio_coding/test/TestAllCodecs.h
+++ b/modules/audio_coding/test/TestAllCodecs.h
@@ -13,7 +13,6 @@
 
 #include <memory>
 
-#include "modules/audio_coding/test/ACMTest.h"
 #include "modules/audio_coding/test/Channel.h"
 #include "modules/audio_coding/test/PCMFile.h"
 
@@ -47,12 +46,12 @@
   size_t payload_size_;
 };
 
-class TestAllCodecs : public ACMTest {
+class TestAllCodecs {
  public:
   explicit TestAllCodecs(int test_mode);
   ~TestAllCodecs();
 
-  void Perform() override;
+  void Perform();
 
  private:
   // The default value of '-1' indicates that the registration is based only on