[FIX] mail: prevent potential memory leak of AudioContext

Before this commit,

The audio context used in media_monitoring was not
closed. Which could lead to memory leaks.

The source was not connected to the destination in the
script processor (used in old browsers that do not support
audioWorklets), which would prevent the monitored audio to be used as
an audio source.

closes odoo/odoo#119124

X-original-commit: f1c3f78dd6e17fe2a3f5a01d8510ca4343b880fe
Signed-off-by: Thanh Dodeur (tso) <tso@odoo.com>
Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>

addons/mail/static/src/rtc/media_monitoring.js

@@ -17,7 +17,7 @@ const HUMAN_VOICE_FREQUENCY_RANGE = [80, 1000];
  *          last time the threshold was exceeded to go back to inactive state, this prevents
  *          stuttering when the speech volume oscillates around the threshold value.
  * @param {function(boolean):void} [processorOptions.onThreshold] a function to be called when the threshold is passed
- * @param {function(number):void} [processorOptions] a function to be called at each tics
+ * @param {function(number):void} [processorOptions.onTic] a function to be called at each tics
  * @param {number} [processorOptions.volumeThreshold] the normalized minimum value for audio detection
  * @returns {Object} returnValue
  * @returns {function} returnValue.disconnect callback to cleanly end the monitoring
@@ -42,10 +42,11 @@ export async function monitorAudio(track, processorOptions) {
         processor = _loadScriptProcessor(source, audioContext, processorOptions);
     }
 
-    return () => {
+    return async () => {
         processor.disconnect();
         source.disconnect();
         monitoredTrack.stop();
+        await audioContext.close();
     };
 }
 
@@ -77,6 +78,7 @@ function _loadScriptProcessor(
     source.connect(analyser);
     const scriptProcessorNode = audioContext.createScriptProcessor(bitSize, 1, 1);
     analyser.connect(scriptProcessorNode);
+    analyser.connect(audioContext.destination);
     analyser.fftsize = bitSize;
     scriptProcessorNode.connect(audioContext.destination);
 
@@ -155,7 +157,8 @@ async function _loadAudioWorkletProcessor(
             postAllTics: !!onTic,
         },
     });
-    source.connect(thresholdProcessor).connect(audioContext.destination);
+    source.connect(thresholdProcessor);
+    source.connect(audioContext.destination);
     thresholdProcessor.port.onmessage = (event) => {
         const { isAboveThreshold, volume } = event.data;
         if (isAboveThreshold !== undefined) {