Use preferred channel layout on macOS instead of total channel count.

media/base/channel_layout.cc

 // Copyright (c) 2012 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/channel_layout.h"
 
 #include <stddef.h>
 
 #include "base/logging.h"
 #include "base/macros.h"
@@ skipping 142 matching lines @@
     {  0  , 1  , 2  , -1  , -1 , -1 , -1    , -1    , -1 , -1 , -1 },
 
     // CHANNEL_LAYOUT_4_1_QUAD_SIDE
     {  0  , 1  , -1 ,  4  , -1 , -1 , -1    , -1    , -1 , 2  ,  3 },
 
     // FL | FR | FC | LFE | BL | BR | FLofC | FRofC | BC | SL | SR
 };
 
 int ChannelLayoutToChannelCount(ChannelLayout layout) {
   DCHECK_LT(static_cast<size_t>(layout), arraysize(kLayoutToChannels));
+  DCHECK_LE(kLayoutToChannels[layout], kMaxConcurrentChannels);
   return kLayoutToChannels[layout];
 }
 
 // Converts a channel count into a channel layout.
 ChannelLayout GuessChannelLayout(int channels) {
   switch (channels) {
     case 1:
       return CHANNEL_LAYOUT_MONO;
     case 2:
       return CHANNEL_LAYOUT_STEREO;
@@ skipping 86 matching lines @@
     case CHANNEL_LAYOUT_STEREO_AND_KEYBOARD_MIC:
       return "STEREO_AND_KEYBOARD_MIC";
     case CHANNEL_LAYOUT_4_1_QUAD_SIDE:
       return "4.1_QUAD_SIDE";
   }
   NOTREACHED() << "Invalid channel layout provided: " << layout;
   return "";
 }
 
 }  // namespace media