Enable pcm_s32le audio decoding.

media/ffmpeg/ffmpeg_common_unittest.cc

Index: media/ffmpeg/ffmpeg_common_unittest.cc
diff --git a/media/ffmpeg/ffmpeg_common_unittest.cc b/media/ffmpeg/ffmpeg_common_unittest.cc
index aa8a06d9de7d9b90657ca2cd542ba487b83a7619..9a735872cf3ca4fb796bc1292414870bcd35a94d 100644
--- a/media/ffmpeg/ffmpeg_common_unittest.cc
+++ b/media/ffmpeg/ffmpeg_common_unittest.cc
@@ -161,17 +161,24 @@ TEST_F(FFmpegCommonTest, VerifyFormatSizes) {
   for (AVSampleFormat format = AV_SAMPLE_FMT_NONE;
        format < AV_SAMPLE_FMT_NB;
        format = static_cast<AVSampleFormat>(format + 1)) {
-    SampleFormat sample_format = AVSampleFormatToSampleFormat(format);
-    if (sample_format == kUnknownSampleFormat) {
-      // This format not supported, so skip it.
-      continue;
+    std::vector<AVCodecID> codec_ids(1, AV_CODEC_ID_NONE);
+    if (format == AV_SAMPLE_FMT_S32)
+      codec_ids.push_back(AV_CODEC_ID_PCM_S24LE);
+    for (const auto& codec_id : codec_ids) {
+      SampleFormat sample_format =
+          AVSampleFormatToSampleFormat(format, codec_id);
+      if (sample_format == kUnknownSampleFormat) {
+        // This format not supported, so skip it.
+        continue;
+      }
+
+      // Have FFMpeg compute the size of a buffer of 1 channel / 1 frame
+      // with 1 byte alignment to make sure the sizes match.
+      int single_buffer_size =
+          av_samples_get_buffer_size(NULL, 1, 1, format, 1);
+      int bytes_per_channel = SampleFormatToBytesPerChannel(sample_format);
+      EXPECT_EQ(bytes_per_channel, single_buffer_size);
     }
-
-    // Have FFMpeg compute the size of a buffer of 1 channel / 1 frame
-    // with 1 byte alignment to make sure the sizes match.
-    int single_buffer_size = av_samples_get_buffer_size(NULL, 1, 1, format, 1);
-    int bytes_per_channel = SampleFormatToBytesPerChannel(sample_format);
-    EXPECT_EQ(bytes_per_channel, single_buffer_size);
   }
 }