Support AudioContextOptions latencyHint as double.

content/shell/renderer/layout_test/layout_test_content_renderer_client.cc

 // Copyright (c) 2014 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/shell/renderer/layout_test/layout_test_content_renderer_client.h"
 
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/memory/ptr_util.h"
@@ skipping 13 matching lines @@
 #include "content/shell/renderer/layout_test/layout_test_render_thread_observer.h"
 #include "content/shell/renderer/layout_test/test_media_stream_renderer_factory.h"
 #include "content/shell/renderer/shell_render_view_observer.h"
 #include "content/shell/test_runner/mock_credential_manager_client.h"
 #include "content/shell/test_runner/web_frame_test_proxy.h"
 #include "content/shell/test_runner/web_test_interfaces.h"
 #include "content/shell/test_runner/web_test_runner.h"
 #include "content/shell/test_runner/web_view_test_proxy.h"
 #include "content/test/mock_webclipboard_impl.h"
 #include "gin/modules/module_registry.h"
+#include "media/base/audio_latency.h"
 #include "media/media_features.h"
+#include "third_party/WebKit/public/platform/WebAudioLatencyHint.h"
 #include "third_party/WebKit/public/platform/WebMediaStreamCenter.h"
 #include "third_party/WebKit/public/web/WebFrameWidget.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebPluginParams.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/WebTestingSupport.h"
 #include "third_party/WebKit/public/web/WebView.h"
 #include "ui/gfx/icc_profile.h"
 #include "v8/include/v8.h"
 
@@ skipping 142 matching lines @@
 }
 
 WebMIDIAccessor*
 LayoutTestContentRendererClient::OverrideCreateMIDIAccessor(
     WebMIDIAccessorClient* client) {
   test_runner::WebTestInterfaces* interfaces =
       LayoutTestRenderThreadObserver::GetInstance()->test_interfaces();
   return interfaces->CreateMIDIAccessor(client);
 }
 
-WebAudioDevice* LayoutTestContentRendererClient::OverrideCreateAudioDevice() {
+WebAudioDevice* LayoutTestContentRendererClient::OverrideCreateAudioDevice(
+    const blink::WebAudioLatencyHint& latency_hint) {
+  const double hw_buffer_size = 128;
+  const double hw_sample_rate = 44100;
+  double buffer_size = 0;
+  switch (latency_hint.Category()) {
+    case blink::WebAudioLatencyHint::kCategoryInteractive:
+      buffer_size =
+          media::AudioLatency::GetInteractiveBufferSize(hw_buffer_size);
+      break;
+    case blink::WebAudioLatencyHint::kCategoryBalanced:
+      buffer_size =
+          media::AudioLatency::GetRtcBufferSize(hw_sample_rate, hw_buffer_size);
+      break;
+    case blink::WebAudioLatencyHint::kCategoryPlayback:
+      buffer_size =
+          media::AudioLatency::GetHighLatencyBufferSize(hw_sample_rate, 0);
+      break;
+    case blink::WebAudioLatencyHint::kCategoryExact:
+      // TODO(andrew.macpherson@soundtrap.com): http://crbug.com/708917
+      buffer_size = std::min(
+          4096, media::AudioLatency::GetExactBufferSize(
+                    base::TimeDelta::FromSecondsD(latency_hint.Seconds()),
+                    hw_sample_rate, hw_buffer_size));
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
   test_runner::WebTestInterfaces* interfaces =
       LayoutTestRenderThreadObserver::GetInstance()->test_interfaces();
-  return interfaces->CreateAudioDevice(44100, 128);
+  return interfaces->CreateAudioDevice(hw_sample_rate, buffer_size);
 }
 
 WebClipboard* LayoutTestContentRendererClient::OverrideWebClipboard() {
   if (!clipboard_)
     clipboard_.reset(new MockWebClipboardImpl);
   return clipboard_.get();
 }
 
 WebThemeEngine* LayoutTestContentRendererClient::OverrideThemeEngine() {
   return LayoutTestRenderThreadObserver::GetInstance()
@@ skipping 67 matching lines @@
           switches::kStableReleaseMode)) {
     blink::WebRuntimeFeatures::EnableTestOnlyFeatures(true);
   }
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kEnableFontAntialiasing)) {
     blink::SetFontAntialiasingEnabledForTest(true);
   }
 }
 
 }  // namespace content