Enable pcm_s32le audio decoding.

media/base/sample_format.cc

 // Copyright 2013 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 "media/base/sample_format.h"
 
 #include "base/logging.h"
 
 namespace media {
 
 int SampleFormatToBytesPerChannel(SampleFormat sample_format) {
   switch (sample_format) {
     case kUnknownSampleFormat:
       return 0;
     case kSampleFormatU8:
       return 1;
     case kSampleFormatS16:
     case kSampleFormatPlanarS16:
       return 2;
+    case kSampleFormatS24:
     case kSampleFormatS32:
     case kSampleFormatF32:
     case kSampleFormatPlanarF32:
     case kSampleFormatPlanarS32:
       return 4;
   }
 
   NOTREACHED() << "Invalid sample format provided: " << sample_format;
   return 0;
 }
 
 const char* SampleFormatToString(SampleFormat sample_format) {
   switch(sample_format) {
     case kUnknownSampleFormat:
       return "Unknown sample format";
     case kSampleFormatU8:
       return "Unsigned 8-bit with bias of 128";
     case kSampleFormatS16:
       return "Signed 16-bit";
+    case kSampleFormatS24:
+      return "Signed 24-bit";
     case kSampleFormatS32:
       return "Signed 32-bit";
     case kSampleFormatF32:
       return "Float 32-bit";
     case kSampleFormatPlanarS16:
       return "Signed 16-bit planar";
     case kSampleFormatPlanarF32:
       return "Float 32-bit planar";
     case kSampleFormatPlanarS32:
       return "Signed 32-bit planar";
   }
   NOTREACHED() << "Invalid sample format provided: " << sample_format;
   return "";
 }
 
 }  // namespace media