diff --git a/webrtc/modules/audio_coding/acm2/audio_coding_module_impl.cc b/webrtc/modules/audio_coding/acm2/audio_coding_module_impl.cc
index 254c2f420b..f00b2432f2 100644
--- a/webrtc/modules/audio_coding/acm2/audio_coding_module_impl.cc
+++ b/webrtc/modules/audio_coding/acm2/audio_coding_module_impl.cc
@@ -104,7 +104,6 @@ void ConvertEncodedInfoToFragmentationHeader(
 class RawAudioEncoderWrapper final : public AudioEncoder {
  public:
   RawAudioEncoderWrapper(AudioEncoder* enc) : enc_(enc) {}
-  size_t MaxEncodedBytes() const override { return enc_->MaxEncodedBytes(); }
   int SampleRateHz() const override { return enc_->SampleRateHz(); }
   size_t NumChannels() const override { return enc_->NumChannels(); }
   int RtpTimestampRateHz() const override { return enc_->RtpTimestampRateHz(); }
@@ -120,13 +119,6 @@ class RawAudioEncoderWrapper final : public AudioEncoder {
                          rtc::Buffer* encoded) override {
     return enc_->Encode(rtp_timestamp, audio, encoded);
   }
-  EncodedInfo EncodeInternal(uint32_t rtp_timestamp,
-                             rtc::ArrayView<const int16_t> audio,
-                             size_t max_encoded_bytes,
-                             uint8_t* encoded) override {
-    return enc_->EncodeInternal(rtp_timestamp, audio, max_encoded_bytes,
-                                encoded);
-  }
   void Reset() override { return enc_->Reset(); }
   bool SetFec(bool enable) override { return enc_->SetFec(enable); }
   bool SetDtx(bool enable) override { return enc_->SetDtx(enable); }
diff --git a/webrtc/modules/audio_coding/codecs/audio_encoder.cc b/webrtc/modules/audio_coding/codecs/audio_encoder.cc
index 6f793e2531..fa262c4644 100644
--- a/webrtc/modules/audio_coding/codecs/audio_encoder.cc
+++ b/webrtc/modules/audio_coding/codecs/audio_encoder.cc
@@ -37,55 +37,6 @@ AudioEncoder::EncodedInfo AudioEncoder::Encode(
   return info;
 }
 
-AudioEncoder::EncodedInfo AudioEncoder::Encode(
-    uint32_t rtp_timestamp,
-    rtc::ArrayView<const int16_t> audio,
-    size_t max_encoded_bytes,
-    uint8_t* encoded) {
-  return DEPRECATED_Encode(rtp_timestamp, audio, max_encoded_bytes, encoded);
-}
-
-AudioEncoder::EncodedInfo AudioEncoder::DEPRECATED_Encode(
-    uint32_t rtp_timestamp,
-    rtc::ArrayView<const int16_t> audio,
-    size_t max_encoded_bytes,
-    uint8_t* encoded) {
-  TRACE_EVENT0("webrtc", "AudioEncoder::Encode");
-  RTC_CHECK_EQ(audio.size(),
-               static_cast<size_t>(NumChannels() * SampleRateHz() / 100));
-  EncodedInfo info =
-      EncodeInternal(rtp_timestamp, audio, max_encoded_bytes, encoded);
-  RTC_CHECK_LE(info.encoded_bytes, max_encoded_bytes);
-  return info;
-}
-
-AudioEncoder::EncodedInfo AudioEncoder::EncodeImpl(
-    uint32_t rtp_timestamp,
-    rtc::ArrayView<const int16_t> audio,
-    rtc::Buffer* encoded)
-{
-  EncodedInfo info;
-  encoded->AppendData(MaxEncodedBytes(), [&] (rtc::ArrayView<uint8_t> encoded) {
-      info = EncodeInternal(rtp_timestamp, audio,
-                            encoded.size(), encoded.data());
-      return info.encoded_bytes;
-    });
-  return info;
-}
-
-AudioEncoder::EncodedInfo AudioEncoder::EncodeInternal(
-    uint32_t rtp_timestamp,
-    rtc::ArrayView<const int16_t> audio,
-    size_t max_encoded_bytes,
-    uint8_t* encoded)
-{
-  rtc::Buffer temp_buffer;
-  EncodedInfo info = EncodeImpl(rtp_timestamp, audio, &temp_buffer);
-  RTC_DCHECK_LE(temp_buffer.size(), max_encoded_bytes);
-  std::memcpy(encoded, temp_buffer.data(), info.encoded_bytes);
-  return info;
-}
-
 bool AudioEncoder::SetFec(bool enable) {
   return !enable;
 }
@@ -104,4 +55,9 @@ void AudioEncoder::SetProjectedPacketLossRate(double fraction) {}
 
 void AudioEncoder::SetTargetBitrate(int target_bps) {}
 
+size_t AudioEncoder::MaxEncodedBytes() const {
+  RTC_CHECK(false);
+  return 0;
+}
+
 }  // namespace webrtc
diff --git a/webrtc/modules/audio_coding/codecs/audio_encoder.h b/webrtc/modules/audio_coding/codecs/audio_encoder.h
index 3fdee259ce..58d9fff451 100644
--- a/webrtc/modules/audio_coding/codecs/audio_encoder.h
+++ b/webrtc/modules/audio_coding/codecs/audio_encoder.h
@@ -52,14 +52,6 @@ class AudioEncoder {
 
   virtual ~AudioEncoder() = default;
 
-  // Returns the maximum number of bytes that can be produced by the encoder
-  // at each Encode() call. The caller can use the return value to determine
-  // the size of the buffer that needs to be allocated. This value is allowed
-  // to depend on encoder parameters like bitrate, frame size etc., so if
-  // any of these change, the caller of Encode() is responsible for checking
-  // that the buffer is large enough by calling MaxEncodedBytes() again.
-  virtual size_t MaxEncodedBytes() const = 0;
-
   // Returns the input sample rate in Hz and the number of input channels.
   // These are constants set at instantiation time.
   virtual int SampleRateHz() const = 0;
@@ -95,33 +87,6 @@ class AudioEncoder {
                      rtc::ArrayView<const int16_t> audio,
                      rtc::Buffer* encoded);
 
-  // Deprecated interface to Encode (remove eventually, bug 5591). May incur a
-  // copy. The encoder produces zero or more bytes of output in |encoded| and
-  // returns additional encoding information.  The caller is responsible for
-  // making sure that |max_encoded_bytes| is not smaller than the number of
-  // bytes actually produced by the encoder.
-  RTC_DEPRECATED EncodedInfo Encode(uint32_t rtp_timestamp,
-                                    rtc::ArrayView<const int16_t> audio,
-                                    size_t max_encoded_bytes,
-                                    uint8_t* encoded);
-
-  EncodedInfo DEPRECATED_Encode(uint32_t rtp_timestamp,
-                                rtc::ArrayView<const int16_t> audio,
-                                size_t max_encoded_bytes,
-                                uint8_t* encoded);
-
-  // Deprecated interface EncodeInternal (see bug 5591). May incur a copy.
-  // Subclasses implement this to perform the actual encoding. Called by
-  // Encode(). By default, this is implemented as a call to the newer
-  // EncodeImpl() that accepts an rtc::Buffer instead of a raw pointer.
-  // That version is protected, so see below. At least one of EncodeInternal
-  // or EncodeImpl _must_ be implemented by a subclass.
-  virtual EncodedInfo EncodeInternal(
-      uint32_t rtp_timestamp,
-      rtc::ArrayView<const int16_t> audio,
-      size_t max_encoded_bytes,
-      uint8_t* encoded);
-
   // Resets the encoder to its starting state, discarding any input that has
   // been fed to the encoder but not yet emitted in a packet.
   virtual void Reset() = 0;
@@ -162,13 +127,19 @@ class AudioEncoder {
 
  protected:
   // Subclasses implement this to perform the actual encoding. Called by
-  // Encode(). For compatibility reasons, this is implemented by default as a
-  // call to the older interface EncodeInternal(). At least one of
-  // EncodeInternal or EncodeImpl _must_ be implemented by a
-  // subclass. Preferably this one.
+  // Encode().
   virtual EncodedInfo EncodeImpl(uint32_t rtp_timestamp,
                                  rtc::ArrayView<const int16_t> audio,
-                                 rtc::Buffer* encoded);
+                                 rtc::Buffer* encoded) = 0;
+
+ private:
+  // This function is deprecated. It was used to return the maximum number of
+  // bytes that can be produced by the encoder at each Encode() call.  Since the
+  // Encode interface was changed to use rtc::Buffer, this is no longer
+  // applicable. It is only kept in to avoid breaking subclasses that still have
+  // it implemented (with the override attribute). It will be removed as soon
+  // as these subclasses have been given a chance to change.
+  virtual size_t MaxEncodedBytes() const;
 };
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_AUDIO_CODING_CODECS_AUDIO_ENCODER_H_
diff --git a/webrtc/modules/audio_coding/codecs/audio_encoder_unittest.cc b/webrtc/modules/audio_coding/codecs/audio_encoder_unittest.cc
deleted file mode 100644
index 71ffcde323..0000000000
--- a/webrtc/modules/audio_coding/codecs/audio_encoder_unittest.cc
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- *  Copyright (c) 2016 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.
- */
-
-#include "testing/gtest/include/gtest/gtest.h"
-#include "webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.h"
-
-using ::testing::_;
-using ::testing::Invoke;
-using ::testing::Return;
-
-namespace webrtc {
-
-TEST(AudioEncoderTest, EncodeInternalRedirectsOk) {
-  const size_t kPayloadSize = 16;
-  const uint8_t payload[kPayloadSize] =
-      {0xf, 0xe, 0xd, 0xc, 0xb, 0xa, 0x9, 0x8,
-       0x7, 0x6, 0x5, 0x4, 0x3, 0x2, 0x1, 0x0};
-
-  MockAudioEncoderDeprecated old_impl;
-  MockAudioEncoder new_impl;
-  MockAudioEncoderBase* impls[] = { &old_impl, &new_impl };
-  for (auto* impl : impls) {
-    EXPECT_CALL(*impl, Die());
-    EXPECT_CALL(*impl, MaxEncodedBytes())
-        .WillRepeatedly(Return(kPayloadSize * 2));
-    EXPECT_CALL(*impl, NumChannels()).WillRepeatedly(Return(1));
-    EXPECT_CALL(*impl, SampleRateHz()).WillRepeatedly(Return(8000));
-  }
-
-  EXPECT_CALL(old_impl, EncodeInternal(_, _, _, _)).WillOnce(
-      Invoke(MockAudioEncoderDeprecated::CopyEncoding(payload)));
-
-  EXPECT_CALL(new_impl, EncodeImpl(_, _, _)).WillOnce(
-      Invoke(MockAudioEncoder::CopyEncoding(payload)));
-
-  int16_t audio[80];
-  uint8_t output_array[kPayloadSize * 2];
-  rtc::Buffer output_buffer;
-
-  AudioEncoder* old_encoder = &old_impl;
-  AudioEncoder* new_encoder = &new_impl;
-  auto old_info = old_encoder->Encode(0, audio, &output_buffer);
-  auto new_info = new_encoder->DEPRECATED_Encode(0, audio,
-                                                 kPayloadSize * 2,
-                                                 output_array);
-
-  EXPECT_EQ(old_info.encoded_bytes, kPayloadSize);
-  EXPECT_EQ(new_info.encoded_bytes, kPayloadSize);
-  EXPECT_EQ(output_buffer.size(), kPayloadSize);
-
-  for (size_t i = 0; i != kPayloadSize; ++i) {
-    EXPECT_EQ(output_buffer.data()[i], payload[i]);
-    EXPECT_EQ(output_array[i], payload[i]);
-  }
-}
-
-}  // namespace webrtc
diff --git a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
index 2f80944be2..04b635d8ca 100644
--- a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
+++ b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
@@ -72,13 +72,6 @@ AudioEncoderCng::AudioEncoderCng(Config&& config)
 
 AudioEncoderCng::~AudioEncoderCng() = default;
 
-size_t AudioEncoderCng::MaxEncodedBytes() const {
-  const size_t max_encoded_bytes_active = speech_encoder_->MaxEncodedBytes();
-  const size_t max_encoded_bytes_passive =
-      rtc::CheckedDivExact(kMaxFrameSizeMs, 10) * SamplesPer10msFrame();
-  return std::max(max_encoded_bytes_active, max_encoded_bytes_passive);
-}
-
 int AudioEncoderCng::SampleRateHz() const {
   return speech_encoder_->SampleRateHz();
 }
diff --git a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.h b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.h
index 1384cd511e..b52665d9c0 100644
--- a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.h
+++ b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.h
@@ -52,7 +52,6 @@ class AudioEncoderCng final : public AudioEncoder {
   explicit AudioEncoderCng(Config&& config);
   ~AudioEncoderCng() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   int RtpTimestampRateHz() const override;
diff --git a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng_unittest.cc b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng_unittest.cc
index 8f30d783ae..8b80d2181d 100644
--- a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng_unittest.cc
+++ b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng_unittest.cc
@@ -25,7 +25,6 @@ using ::testing::Invoke;
 namespace webrtc {
 
 namespace {
-static const size_t kMockMaxEncodedBytes = 1000;
 static const size_t kMaxNumSamples = 48 * 10 * 2;  // 10 ms @ 48 kHz stereo.
 static const size_t kMockReturnEncodedBytes = 17;
 static const int kCngPayloadType = 18;
@@ -74,8 +73,6 @@ class AudioEncoderCngTest : public ::testing::Test {
       // as long as it is smaller than 10.
       EXPECT_CALL(*mock_encoder_, Max10MsFramesInAPacket())
           .WillOnce(Return(1u));
-      EXPECT_CALL(*mock_encoder_, MaxEncodedBytes())
-          .WillRepeatedly(Return(kMockMaxEncodedBytes));
     }
     cng_.reset(new AudioEncoderCng(std::move(config)));
   }
@@ -90,8 +87,8 @@ class AudioEncoderCngTest : public ::testing::Test {
   }
 
   // Expect |num_calls| calls to the encoder, all successful. The last call
-  // claims to have encoded |kMockMaxEncodedBytes| bytes, and all the preceding
-  // ones 0 bytes.
+  // claims to have encoded |kMockReturnEncodedBytes| bytes, and all the
+  // preceding ones 0 bytes.
   void ExpectEncodeCalls(size_t num_calls) {
     InSequence s;
     AudioEncoder::EncodedInfo info;
diff --git a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
index a24b1526fd..e4da8d7440 100644
--- a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
+++ b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
@@ -52,10 +52,6 @@ AudioEncoderPcm::AudioEncoderPcm(const Config& config, int sample_rate_hz)
 
 AudioEncoderPcm::~AudioEncoderPcm() = default;
 
-size_t AudioEncoderPcm::MaxEncodedBytes() const {
-  return full_frame_samples_ * BytesPerSample();
-}
-
 int AudioEncoderPcm::SampleRateHz() const {
   return sample_rate_hz_;
 }
@@ -93,7 +89,7 @@ AudioEncoder::EncodedInfo AudioEncoderPcm::EncodeImpl(
   info.encoded_timestamp = first_timestamp_in_buffer_;
   info.payload_type = payload_type_;
   info.encoded_bytes =
-      encoded->AppendData(MaxEncodedBytes(),
+      encoded->AppendData(full_frame_samples_ * BytesPerSample(),
                           [&] (rtc::ArrayView<uint8_t> encoded) {
                             return EncodeCall(&speech_buffer_[0],
                                               full_frame_samples_,
diff --git a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.h b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.h
index 6b3cebfb33..eb5ad02878 100644
--- a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.h
+++ b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.h
@@ -35,7 +35,6 @@ class AudioEncoderPcm : public AudioEncoder {
 
   ~AudioEncoderPcm() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   size_t Num10MsFramesInNextPacket() const override;
diff --git a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
index 9256518445..256013266d 100644
--- a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
+++ b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
@@ -60,10 +60,6 @@ AudioEncoderG722::AudioEncoderG722(const CodecInst& codec_inst)
 
 AudioEncoderG722::~AudioEncoderG722() = default;
 
-size_t AudioEncoderG722::MaxEncodedBytes() const {
-  return SamplesPerChannel() / 2 * num_channels_;
-}
-
 int AudioEncoderG722::SampleRateHz() const {
   return kSampleRateHz;
 }
diff --git a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.h b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.h
index dec87b2b7a..b3f6965fff 100644
--- a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.h
+++ b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.h
@@ -35,7 +35,6 @@ class AudioEncoderG722 final : public AudioEncoder {
   explicit AudioEncoderG722(const CodecInst& codec_inst);
   ~AudioEncoderG722() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   int RtpTimestampRateHz() const override;
@@ -44,7 +43,7 @@ class AudioEncoderG722 final : public AudioEncoder {
   int GetTargetBitrate() const override;
   void Reset() override;
 
-protected:
+ protected:
   EncodedInfo EncodeImpl(uint32_t rtp_timestamp,
                          rtc::ArrayView<const int16_t> audio,
                          rtc::Buffer* encoded) override;
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
index c7d7411c45..45401a1280 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
+++ b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
@@ -56,10 +56,6 @@ AudioEncoderIlbc::~AudioEncoderIlbc() {
   RTC_CHECK_EQ(0, WebRtcIlbcfix_EncoderFree(encoder_));
 }
 
-size_t AudioEncoderIlbc::MaxEncodedBytes() const {
-  return RequiredOutputSizeBytes();
-}
-
 int AudioEncoderIlbc::SampleRateHz() const {
   return kSampleRateHz;
 }
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.h b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.h
index 27329bbc4e..63639860f4 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.h
+++ b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.h
@@ -34,7 +34,6 @@ class AudioEncoderIlbc final : public AudioEncoder {
   explicit AudioEncoderIlbc(const CodecInst& codec_inst);
   ~AudioEncoderIlbc() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   size_t Num10MsFramesInNextPacket() const override;
diff --git a/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t.h b/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t.h
index 0da8ed71d6..afe38d7940 100644
--- a/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t.h
+++ b/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t.h
@@ -56,7 +56,6 @@ class AudioEncoderIsacT final : public AudioEncoder {
       const rtc::scoped_refptr<LockedIsacBandwidthInfo>& bwinfo);
   ~AudioEncoderIsacT() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   size_t Num10MsFramesInNextPacket() const override;
diff --git a/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t_impl.h b/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t_impl.h
index 1debbeb903..1f95e5980e 100644
--- a/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t_impl.h
+++ b/webrtc/modules/audio_coding/codecs/isac/audio_encoder_isac_t_impl.h
@@ -79,11 +79,6 @@ AudioEncoderIsacT<T>::~AudioEncoderIsacT() {
   RTC_CHECK_EQ(0, T::Free(isac_state_));
 }
 
-template <typename T>
-size_t AudioEncoderIsacT<T>::MaxEncodedBytes() const {
-  return kSufficientEncodeBufferSizeBytes;
-}
-
 template <typename T>
 int AudioEncoderIsacT<T>::SampleRateHz() const {
   return T::EncSampRate(isac_state_);
diff --git a/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.cc b/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.cc
index 52849691ac..a674eba660 100644
--- a/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.cc
+++ b/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.cc
@@ -49,26 +49,4 @@ AudioEncoder::EncodedInfo MockAudioEncoder::CopyEncoding::operator()(
   return info_;
 }
 
-MockAudioEncoderDeprecated::CopyEncoding::CopyEncoding(
-    AudioEncoder::EncodedInfo info,
-    rtc::ArrayView<const uint8_t> payload)
-    : info_(info), payload_(payload) { }
-
-MockAudioEncoderDeprecated::CopyEncoding::CopyEncoding(
-    rtc::ArrayView<const uint8_t> payload)
-    : payload_(payload) {
-  info_.encoded_bytes = payload_.size();
-}
-
-AudioEncoder::EncodedInfo MockAudioEncoderDeprecated::CopyEncoding::operator()(
-    uint32_t timestamp,
-    rtc::ArrayView<const int16_t> audio,
-    size_t max_bytes_encoded,
-    uint8_t* encoded) {
-  RTC_CHECK(encoded);
-  RTC_CHECK_LE(info_.encoded_bytes, payload_.size());
-  std::memcpy(encoded, payload_.data(), info_.encoded_bytes);
-  return info_;
-}
-
 }  // namespace webrtc
diff --git a/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.h b/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.h
index 58a1e756f9..f898877c19 100644
--- a/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.h
+++ b/webrtc/modules/audio_coding/codecs/mock/mock_audio_encoder.h
@@ -18,12 +18,11 @@
 
 namespace webrtc {
 
-class MockAudioEncoderBase : public AudioEncoder {
+class MockAudioEncoder : public AudioEncoder {
  public:
-  ~MockAudioEncoderBase() override { Die(); }
+  ~MockAudioEncoder() override { Die(); }
   MOCK_METHOD0(Die, void());
   MOCK_METHOD1(Mark, void(std::string desc));
-  MOCK_CONST_METHOD0(MaxEncodedBytes, size_t());
   MOCK_CONST_METHOD0(SampleRateHz, int());
   MOCK_CONST_METHOD0(NumChannels, size_t());
   MOCK_CONST_METHOD0(RtpTimestampRateHz, int());
@@ -39,10 +38,7 @@ class MockAudioEncoderBase : public AudioEncoder {
   MOCK_METHOD1(SetTargetBitrate, void(int target_bps));
   MOCK_METHOD1(SetMaxBitrate, void(int max_bps));
   MOCK_METHOD1(SetMaxPayloadSize, void(int max_payload_size_bytes));
-};
 
-class MockAudioEncoder final : public MockAudioEncoderBase {
- public:
   // Note, we explicitly chose not to create a mock for the Encode method.
   MOCK_METHOD3(EncodeImpl,
                EncodedInfo(uint32_t timestamp,
@@ -89,36 +85,6 @@ class MockAudioEncoder final : public MockAudioEncoderBase {
     AudioEncoder::EncodedInfo info_;
     rtc::ArrayView<const uint8_t> payload_;
   };
-
-};
-
-class MockAudioEncoderDeprecated final : public MockAudioEncoderBase {
- public:
-  // Note, we explicitly chose not to create a mock for the Encode method.
-  MOCK_METHOD4(EncodeInternal,
-               EncodedInfo(uint32_t timestamp,
-                           rtc::ArrayView<const int16_t> audio,
-                           size_t max_encoded_bytes,
-                           uint8_t* encoded));
-
-  // A functor like MockAudioEncoder::CopyEncoding above, but which has the
-  // deprecated Encode signature. Currently only used in one test and should be
-  // removed once that backwards compatibility is.
-  class CopyEncoding {
-   public:
-    CopyEncoding(AudioEncoder::EncodedInfo info,
-                 rtc::ArrayView<const uint8_t> payload);
-
-    CopyEncoding(rtc::ArrayView<const uint8_t> payload);
-
-    AudioEncoder::EncodedInfo operator()(uint32_t timestamp,
-                                         rtc::ArrayView<const int16_t> audio,
-                                         size_t max_bytes_encoded,
-                                         uint8_t* encoded);
-   private:
-    AudioEncoder::EncodedInfo info_;
-    rtc::ArrayView<const uint8_t> payload_;
-  };
 };
 
 }  // namespace webrtc
diff --git a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
index a599e291d4..799d122fe8 100644
--- a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
+++ b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
@@ -100,16 +100,6 @@ AudioEncoderOpus::~AudioEncoderOpus() {
   RTC_CHECK_EQ(0, WebRtcOpus_EncoderFree(inst_));
 }
 
-size_t AudioEncoderOpus::MaxEncodedBytes() const {
-  // Calculate the number of bytes we expect the encoder to produce,
-  // then multiply by two to give a wide margin for error.
-  const size_t bytes_per_millisecond =
-      static_cast<size_t>(config_.bitrate_bps / (1000 * 8) + 1);
-  const size_t approx_encoded_bytes =
-      Num10msFramesPerPacket() * 10 * bytes_per_millisecond;
-  return 2 * approx_encoded_bytes;
-}
-
 int AudioEncoderOpus::SampleRateHz() const {
   return kSampleRateHz;
 }
@@ -198,7 +188,7 @@ AudioEncoder::EncodedInfo AudioEncoderOpus::EncodeImpl(
   RTC_CHECK_EQ(input_buffer_.size(),
                Num10msFramesPerPacket() * SamplesPer10msFrame());
 
-  const size_t max_encoded_bytes = MaxEncodedBytes();
+  const size_t max_encoded_bytes = SufficientOutputBufferSize();
   EncodedInfo info;
   info.encoded_bytes =
       encoded->AppendData(
@@ -231,6 +221,16 @@ size_t AudioEncoderOpus::SamplesPer10msFrame() const {
   return rtc::CheckedDivExact(kSampleRateHz, 100) * config_.num_channels;
 }
 
+size_t AudioEncoderOpus::SufficientOutputBufferSize() const {
+  // Calculate the number of bytes we expect the encoder to produce,
+  // then multiply by two to give a wide margin for error.
+  const size_t bytes_per_millisecond =
+      static_cast<size_t>(config_.bitrate_bps / (1000 * 8) + 1);
+  const size_t approx_encoded_bytes =
+      Num10msFramesPerPacket() * 10 * bytes_per_millisecond;
+  return 2 * approx_encoded_bytes;
+}
+
 // If the given config is OK, recreate the Opus encoder instance with those
 // settings, save the config, and return true. Otherwise, do nothing and return
 // false.
diff --git a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.h b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.h
index 3f11af1f9e..8900659f48 100644
--- a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.h
+++ b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.h
@@ -54,7 +54,6 @@ class AudioEncoderOpus final : public AudioEncoder {
   explicit AudioEncoderOpus(const CodecInst& codec_inst);
   ~AudioEncoderOpus() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   size_t Num10MsFramesInNextPacket() const override;
@@ -79,7 +78,7 @@ class AudioEncoderOpus final : public AudioEncoder {
   ApplicationMode application() const { return config_.application; }
   bool dtx_enabled() const { return config_.dtx_enabled; }
 
-protected:
+ protected:
   EncodedInfo EncodeImpl(uint32_t rtp_timestamp,
                          rtc::ArrayView<const int16_t> audio,
                          rtc::Buffer* encoded) override;
@@ -87,6 +86,7 @@ protected:
  private:
   size_t Num10msFramesPerPacket() const;
   size_t SamplesPer10msFrame() const;
+  size_t SufficientOutputBufferSize() const;
   bool RecreateEncoderInstance(const Config& config);
 
   Config config_;
diff --git a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
index b4e95d3b08..7c48c0c60e 100644
--- a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
+++ b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc
@@ -30,10 +30,6 @@ AudioEncoderCopyRed::AudioEncoderCopyRed(Config&& config)
 
 AudioEncoderCopyRed::~AudioEncoderCopyRed() = default;
 
-size_t AudioEncoderCopyRed::MaxEncodedBytes() const {
-  return 2 * speech_encoder_->MaxEncodedBytes();
-}
-
 int AudioEncoderCopyRed::SampleRateHz() const {
   return speech_encoder_->SampleRateHz();
 }
diff --git a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.h b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.h
index a67ae486bb..06d0fdeeca 100644
--- a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.h
+++ b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.h
@@ -37,7 +37,6 @@ class AudioEncoderCopyRed final : public AudioEncoder {
 
   ~AudioEncoderCopyRed() override;
 
-  size_t MaxEncodedBytes() const override;
   int SampleRateHz() const override;
   size_t NumChannels() const override;
   int RtpTimestampRateHz() const override;
@@ -52,7 +51,7 @@ class AudioEncoderCopyRed final : public AudioEncoder {
   void SetProjectedPacketLossRate(double fraction) override;
   void SetTargetBitrate(int target_bps) override;
 
-protected:
+ protected:
   EncodedInfo EncodeImpl(uint32_t rtp_timestamp,
                          rtc::ArrayView<const int16_t> audio,
                          rtc::Buffer* encoded) override;
diff --git a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red_unittest.cc b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red_unittest.cc
index c73cb9f209..22b2ceb5f7 100644
--- a/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red_unittest.cc
+++ b/webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red_unittest.cc
@@ -26,7 +26,6 @@ using ::testing::MockFunction;
 namespace webrtc {
 
 namespace {
-static const size_t kMockMaxEncodedBytes = 1000;
 static const size_t kMaxNumSamples = 48 * 10 * 2;  // 10 ms @ 48 kHz stereo.
 }
 
@@ -46,8 +45,6 @@ class AudioEncoderCopyRedTest : public ::testing::Test {
     EXPECT_CALL(*mock_encoder_, NumChannels()).WillRepeatedly(Return(1U));
     EXPECT_CALL(*mock_encoder_, SampleRateHz())
         .WillRepeatedly(Return(sample_rate_hz_));
-    EXPECT_CALL(*mock_encoder_, MaxEncodedBytes())
-        .WillRepeatedly(Return(kMockMaxEncodedBytes));
   }
 
   void TearDown() override {
diff --git a/webrtc/modules/modules.gyp b/webrtc/modules/modules.gyp
index fd9279e631..8ae5bbb2ed 100644
--- a/webrtc/modules/modules.gyp
+++ b/webrtc/modules/modules.gyp
@@ -167,7 +167,6 @@
             '<(webrtc_root)/tools/tools.gyp:agc_test_utils',
           ],
           'sources': [
-            'audio_coding/codecs/audio_encoder_unittest.cc',
             'audio_coding/codecs/cng/audio_encoder_cng_unittest.cc',
             'audio_coding/acm2/acm_receiver_unittest_oldapi.cc',
             'audio_coding/acm2/audio_coding_module_unittest_oldapi.cc',