Fix multiple memory leaks on Cta608Parser and ResizeObserver (Dash-Industry-Forum#5042)

* fix: Memory leak from Cta608Parser on player.reset() / player.destroy()

* fix: Memory leaks due to VideoModel not reseting + its ResizeObserver and element retention

* fix: Move memory leaks fixes to destroy, not reset

---------

Co-authored-by: Hadrien Lepoutre <hadrien.lepoutre.ext@francetv.fr>

Author: H-L

src/dash/DashAdapter.js

@@ -861,6 +861,10 @@ function DashAdapter() {
         voPeriods = [];
     }
 
+    function destroy() {
+        cea608parser = null;
+    }
+
     /**
      * Checks if the given Preselection is from the given media type
      * @param {object} preselection
@@ -1315,6 +1319,7 @@ function DashAdapter() {
         applyPatchToManifest,
         areMediaInfosEqual,
         convertAdaptationToMediaInfo,
+        destroy,
         getAllMediaInfoForType,
         getAvailabilityStartTime,
         getBandwidthForRepresentation,

src/streaming/MediaPlayer.js

@@ -494,6 +494,16 @@ function MediaPlayer() {
      */
     function destroy() {
         reset();
+
+        if (videoModel) {
+            videoModel.destroy();
+            videoModel = null;
+        }
+
+        if (adapter) {
+            adapter.destroy();
+        }
+
         FactoryMaker.deleteSingletonInstances(context);
     }
 

src/streaming/models/VideoModel.js

@@ -94,10 +94,19 @@ function VideoModel() {
         _disposeResizeObserver();
     }
 
+    function destroy() {
+        reset();
+        element = null;
+        TTMLRenderingDiv = null;
+        vttRenderingDiv = null;
+    }
+
     function _disposeResizeObserver() {
         try {
             if (resizeObserver && element) {
                 resizeObserver.unobserve(element);
+            }
+            if (resizeObserver) {
                 resizeObserver.disconnect();
                 resizeObserver = null;
             }
@@ -208,13 +217,25 @@ function VideoModel() {
     }
 
     function setElement(value) {
+        // In case there was already an element stored in model
+        const isNewElement = element !== value;
+        if (element && !isNewElement) {
+            return;
+        }
+
+        _unregisterResizeObserver(element);
+        element = value;
+
         //add check of value type
-        if (value === null || value === undefined || (value && (/^(VIDEO|AUDIO)$/i).test(value.nodeName))) {
-            element = value;
+        if (value === null || value === undefined) {
+            return;
+        }
+
+        if (value && /^(VIDEO|AUDIO)$/i.test(value.nodeName)) {
             _registerResizeObserver(element);
-        } else {
-            throw VIDEO_MODEL_WRONG_ELEMENT_TYPE;
+            return;
         }
+        throw VIDEO_MODEL_WRONG_ELEMENT_TYPE;
     }
 
     function _registerResizeObserver(element) {
@@ -228,6 +249,15 @@ function VideoModel() {
         }
     }
 
+    function _unregisterResizeObserver(element) {
+        try {
+            if (!resizeObserver || !element) {
+                return;
+            }
+            resizeObserver.unobserve(element);
+        } catch (e) {}
+    }
+
     function setSource(source) {
         if (element) {
             if (source) {
@@ -557,6 +587,7 @@ function VideoModel() {
         addEventListener,
         addTextTrack,
         appendChild,
+        destroy,
         getBufferRange,
         getClientHeight,
         getClientWidth,