Fix/clearkey from ref UI: Check for initData in protData before overw…

…riting (#3942)

* Check for keyPairs in clearkeys object before updating the key session

* Check for length of clearkeys in protData before overwriting init data

src/streaming/protection/controllers/ProtectionController.js

@@ -267,7 +267,7 @@ function ProtectionController(config) {
         if (protectionKeyController.isClearKey(selectedKeySystem)) {
             // For Clearkey: if parameters for generating init data was provided by the user, use them for generating
             // initData and overwrite possible initData indicated in encrypted event (EME)
-            if (keySystemInfo.protData && keySystemInfo.protData.hasOwnProperty('clearkeys')) {
+            if (keySystemInfo.protData && keySystemInfo.protData.hasOwnProperty('clearkeys') && Object.keys(keySystemInfo.protData.clearkeys).length !== 0) {
                 const initData = { kids: Object.keys(keySystemInfo.protData.clearkeys) };
                 keySystemInfo.initData = new TextEncoder().encode(JSON.stringify(initData));
             }