Convert MediaLog from being ref counted to owned by WebMediaPlayer.

testing/libfuzzer/fuzzers/es_parser_mpeg1audio_fuzzer.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/bind.h"
 #include "media/formats/mp2t/es_parser_mpeg1audio.h"
 
 class NullMediaLog : public media::MediaLog {
  public:
   NullMediaLog() {}
+  ~NullMediaLog() override {}
 
-  void DoAddEventLogString(const std::string& event) {}
   void AddEvent(std::unique_ptr<media::MediaLogEvent> event) override {}
 
- protected:
-  virtual ~NullMediaLog() {}
-
  private:
   DISALLOW_COPY_AND_ASSIGN(NullMediaLog);
 };
 
 static void NewAudioConfig(const media::AudioDecoderConfig& config) {}
 static void EmitBuffer(scoped_refptr<media::StreamParserBuffer> buffer) {}
 
 // Entry point for LibFuzzer.
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  scoped_refptr<NullMediaLog> media_log(new NullMediaLog());
-  media::mp2t::EsParserMpeg1Audio es_parser(base::Bind(&NewAudioConfig),
-                                            base::Bind(&EmitBuffer), media_log);
-  if (!es_parser.Parse(data, size, media::kNoTimestamp,
-                       media::kNoDecodeTimestamp())) {
-    return 0;
+  NullMediaLog media_log;
+  media::mp2t::EsParserMpeg1Audio es_parser(
+      base::Bind(&NewAudioConfig), base::Bind(&EmitBuffer), &media_log);
+  if (es_parser.Parse(data, size, media::kNoTimestamp,
+                      media::kNoDecodeTimestamp())) {
+    es_parser.Flush();
   }
-  es_parser.Flush();
   return 0;
 }