Revert "Expose AV1 encoder&decoder from Android SDK."

This reverts commit fedd5029c584e9dc1352434b62a30cd8af2889d8.

Reason for revert: Speculative revert due to crashes in downstream tests on Android.

Original change's description:
> Expose AV1 encoder&decoder from Android SDK.
>
> Bug: None
> Change-Id: Ie32be36da498d4bed2a3cf51aa6abc8838e42da1
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/212024
> Reviewed-by: Xavier Lepaul‎ <xalep@webrtc.org>
> Commit-Queue: Yura Yaroshevich <yura.yaroshevich@gmail.com>
> Cr-Commit-Position: refs/heads/master@{#33743}

TBR=alessiob@webrtc.org,mflodman@webrtc.org,yura.yaroshevich@gmail.com,xalep@webrtc.org

Change-Id: I76171087d1998b9d7573c2b86b1cf9ed65154bbf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: None
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/215324
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33753}

sdk/android/api/org/webrtc/LibaomAv1Encoder.java

@@ -1,27 +0,0 @@
-/*
- *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-package org.webrtc;
-
-public class LibaomAv1Encoder extends WrappedNativeVideoEncoder {
-  @Override
-  public long createNativeVideoEncoder() {
-    return nativeCreateEncoder();
-  }
-
-  static native long nativeCreateEncoder();
-
-  @Override
-  public boolean isHardwareEncoder() {
-    return false;
-  }
-
-  static native boolean nativeIsSupported();
-}