From cddc6125849da05f027d1003dddc3631cd74974c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Calvi=C3=B1o=20S=C3=A1nchez?= <danxuliu@gmail.com>
Date: Fri, 21 Aug 2020 18:23:14 +0200
Subject: [PATCH] Do not use "finally" on promises returned by "getUserMedia"
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"Promise.finally" is available in older browsers for "hand-made"
promises, probably due to a shim or to the code being transpiled (I have
not checked). However, it is not available for internal promises
returned by "navigator.mediaDevices.getUserMedia()".

Moreover, in some browser versions (Firefox >= 58 && <= 68) there seems
to be a clash between the internal promise and the shimed/transpiled
one, as "Promise.finally" is available for "getUserMedia" promises, but
not when used in Nextcloud.

Due to all that "finally" uses were replaced by a function called at the
end of "then" and "catch".

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>
---
 src/components/MediaDevicesPreview.vue  | 40 ++++++++++++++++---------
 src/utils/webrtc/MediaDevicesManager.js |  3 ++
 2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/src/components/MediaDevicesPreview.vue b/src/components/MediaDevicesPreview.vue
index 31462d41a19..cc1d8b16e78 100644
--- a/src/components/MediaDevicesPreview.vue
+++ b/src/components/MediaDevicesPreview.vue
@@ -340,22 +340,28 @@ export default {
 
 			this.pendingGetUserMediaAudioCount = 1
 
+			const resetPendingGetUserMediaAudioCount = () => {
+				const updateAudioStreamAgain = this.pendingGetUserMediaAudioCount > 1
+
+				this.pendingGetUserMediaAudioCount = 0
+
+				if (updateAudioStreamAgain) {
+					this.updateAudioStream()
+				}
+			}
+
 			this.mediaDevicesManager.getUserMedia({ audio: true })
 				.then(stream => {
 					this.setAudioStream(stream)
+
+					resetPendingGetUserMediaAudioCount()
 				})
 				.catch(error => {
 					console.error('Error getting audio stream: ' + error.name + ': ' + error.message)
 					this.audioStreamError = error
 					this.setAudioStream(null)
-				}).finally(() => {
-					const updateAudioStreamAgain = this.pendingGetUserMediaAudioCount > 1
-
-					this.pendingGetUserMediaAudioCount = 0
 
-					if (updateAudioStreamAgain) {
-						this.updateAudioStream()
-					}
+					resetPendingGetUserMediaAudioCount()
 				})
 		},
 
@@ -386,22 +392,28 @@ export default {
 
 			this.pendingGetUserMediaVideoCount = 1
 
+			const resetPendingGetUserMediaVideoCount = () => {
+				const updateVideoStreamAgain = this.pendingGetUserMediaVideoCount > 1
+
+				this.pendingGetUserMediaVideoCount = 0
+
+				if (updateVideoStreamAgain) {
+					this.updateVideoStream()
+				}
+			}
+
 			this.mediaDevicesManager.getUserMedia({ video: true })
 				.then(stream => {
 					this.setVideoStream(stream)
+
+					resetPendingGetUserMediaVideoCount()
 				})
 				.catch(error => {
 					console.error('Error getting video stream: ' + error.name + ': ' + error.message)
 					this.videoStreamError = error
 					this.setVideoStream(null)
-				}).finally(() => {
-					const updateVideoStreamAgain = this.pendingGetUserMediaVideoCount > 1
-
-					this.pendingGetUserMediaVideoCount = 0
 
-					if (updateVideoStreamAgain) {
-						this.updateVideoStream()
-					}
+					resetPendingGetUserMediaVideoCount()
 				})
 		},
 
diff --git a/src/utils/webrtc/MediaDevicesManager.js b/src/utils/webrtc/MediaDevicesManager.js
index 27077aa198f..6d6dc0a685b 100644
--- a/src/utils/webrtc/MediaDevicesManager.js
+++ b/src/utils/webrtc/MediaDevicesManager.js
@@ -303,6 +303,9 @@ MediaDevicesManager.prototype = {
 	 * constraints do not specify a device already. Otherwise the devices in the
 	 * constraints are respected.
 	 *
+	 * For compatibility with older browsers "finally" should not be used on the
+	 * returned Promise.
+	 *
 	 * @param {MediaStreamConstraints} constraints the constraints specifying
 	 *        the media to request
 	 * @returns {Promise} resolved with a MediaStream object when successful, or