GH-2082: Replacing usage of Array.prototype.find/findIndex (#2117)

* GH-2082: Replacing usage of Array.prototype.find and Array.protoype.findIndex with alternate solutions

* GH-2082: Adding eslint rule for restricting usage of findIndex/find methods

.eslintrc.js

@@ -76,6 +76,11 @@ module.exports = {
       'never'
     ],
 
+    'no-restricted-properties': [2,
+      { 'property': 'findIndex' },  // Intended to block usage of Array.prototype.findIndex
+      { 'property': 'find' }        // Intended to block usage of Array.prototype.find
+    ],
+
     'standard/no-callback-literal': 1,
     'import/first': 1,
     'no-var': 1,

src/controller/level-controller.js

@@ -427,7 +427,15 @@ export default class LevelController extends EventHandler {
     }
 
     if (currentLevel.audioGroupIds) {
-      const urlId = currentLevel.audioGroupIds.findIndex((groupId) => groupId === audioGroupId);
+      let urlId = -1;
+
+      for (let i = 0; i < currentLevel.audioGroupIds.length; i++) {
+        if (currentLevel.audioGroupIds[i] === audioGroupId) {
+          urlId = i;
+          break;
+        }
+      }
+
       if (urlId !== currentLevel.urlId) {
         currentLevel.urlId = urlId;
         this.startLoad();

src/controller/timeline-controller.js

@@ -197,7 +197,15 @@ class TimelineController extends EventHandler {
       this.tracks.forEach((track, index) => {
         let textTrack;
         if (index < inUseTracks.length) {
-          const inUseTrack = [].slice.call(inUseTracks).find(inUseTrack => canReuseVttTextTrack(inUseTrack, track));
+          let inUseTrack = null;
+
+          for (let i = 0; i < inUseTracks.length; i++) {
+            if (canReuseVttTextTrack(inUseTracks[i], track)) {
+              inUseTrack = inUseTracks[i];
+              break;
+            }
+          }
+
           // Reuse tracks with the same label, but do not reuse 608/708 tracks
           if (inUseTrack) {
             textTrack = inUseTrack;