From 10306294afa50ffa81382637ea18113884a963ca Mon Sep 17 00:00:00 2001
From: Paul Adenot <paul@paul.cx>
Date: Thu, 28 May 2020 09:52:25 +0000
Subject: [PATCH] Bug 1628779 - Add an entry in about:support for the roundtrip
 audio latency of default devices r=chunmin,fluent-reviewers,flod

Differential Revision: https://phabricator.services.mozilla.com/D75334
---
 toolkit/content/aboutSupport.js                     | 13 +++++++++++++
 .../locales/en-US/toolkit/about/aboutSupport.ftl    |  1 +
 2 files changed, 14 insertions(+)

diff --git a/toolkit/content/aboutSupport.js b/toolkit/content/aboutSupport.js
index a13fd7c062b2..b00a5f54a0f9 100644
--- a/toolkit/content/aboutSupport.js
+++ b/toolkit/content/aboutSupport.js
@@ -919,6 +919,19 @@ var snapshotFormatters = {
     insertBasicInfo("audio-backend", data.currentAudioBackend);
     insertBasicInfo("max-audio-channels", data.currentMaxAudioChannels);
     insertBasicInfo("sample-rate", data.currentPreferredSampleRate);
+    insertBasicInfo("roundtrip-latency", "...");
+    window.windowUtils
+      .defaultDevicesRoundTripLatency()
+      .then(latency => {
+        var latencyString = `${(latency[0] * 1000).toFixed(2)}ms (${(
+          latency[1] * 1000
+        ).toFixed(2)})`;
+        data.defaultDevicesRoundTripLatency = latencyString;
+        document.querySelector(
+          'th[data-l10n-id="roundtrip-latency"]'
+        ).nextSibling.textContent = latencyString;
+      })
+      .catch(e => {});
 
     // Output devices information
     insertDeviceInfo("output", data.audioOutputDevices);
diff --git a/toolkit/locales/en-US/toolkit/about/aboutSupport.ftl b/toolkit/locales/en-US/toolkit/about/aboutSupport.ftl
index 4cd38819c04a..99878aaaccec 100644
--- a/toolkit/locales/en-US/toolkit/about/aboutSupport.ftl
+++ b/toolkit/locales/en-US/toolkit/about/aboutSupport.ftl
@@ -124,6 +124,7 @@ restart-in-safe-mode-label = Restart with Add-ons Disabled…
 audio-backend = Audio Backend
 max-audio-channels = Max Channels
 sample-rate = Preferred Sample Rate
+roundtrip-latency = Roundtrip latency (standard deviation)
 media-title = Media
 media-output-devices-title = Output Devices
 media-input-devices-title = Input Devices