CHANNEL_LAYOUT_2_1 720 content/renderer/renderer_webkitplatformsupport_impl.cc layout = media::CHANNEL_LAYOUT_2_1; CHANNEL_LAYOUT_2_1 201 media/base/channel_layout.cc case CHANNEL_LAYOUT_2_1: CHANNEL_LAYOUT_2_1 463 media/ffmpeg/ffmpeg_common.cc return CHANNEL_LAYOUT_2_1;