Support floating-point audio output for Linux

content/renderer/renderer_blink_platform_impl.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 "content/renderer/renderer_blink_platform_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 730 matching lines @@
           base::StringPiece16(input_device_id)), &session_id)) {
     if (input_channels > 0)
       DLOG(WARNING) << "createAudioDevice(): request for audio input ignored";
 
     input_channels = 0;
   }
 
   // For CHANNEL_LAYOUT_DISCRETE, pass the explicit channel count along with
   // the channel layout when creating an |AudioParameters| object.
   media::AudioParameters params(media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
-                                layout, static_cast<int>(sample_rate), 16,
+                                layout, static_cast<int>(sample_rate), 32,

[DaleCurtis, 2016/11/01 18:51:37]

Drop this change. I can't guarantee it'll plumb properly. Instead set it in
pulse_output/pulse_input.

[Raymond Toy, 2016/11/01 22:01:47]

You're right. It's not plumbed through.

                                 buffer_size);
   params.set_channels_for_discrete(channels);
 
   return new RendererWebAudioDeviceImpl(
       params, callback, session_id, static_cast<url::Origin>(security_origin));
 }
 
 bool RendererBlinkPlatformImpl::loadAudioResource(
     blink::WebAudioBus* destination_bus,
     const char* audio_file_data,
@@ skipping 564 matching lines @@
   return &trial_token_validator_;
 }
 
 void RendererBlinkPlatformImpl::workerContextCreated(
     const v8::Local<v8::Context>& worker) {
   GetContentClient()->renderer()->DidInitializeWorkerContextOnWorkerThread(
       worker);
 }
 
 }  // namespace content