Default UUIDs to an empty list instead of null.

Resolves https://github.com/ajayyy/SponsorBlock/issues/252.

src/content.ts

@@ -13,7 +13,7 @@ var sponsorDataFound = false;
 var previousVideoID = null;
 //the actual sponsorTimes if loaded and UUIDs associated with them
 var sponsorTimes = null;
-var UUIDs = null;
+var UUIDs = [];
 //what video id are these sponsors for
 var sponsorVideoID = null;
 
@@ -215,7 +215,7 @@ function resetValues() {
 
     //reset sponsor times
     sponsorTimes = null;
-    UUIDs = null;
+    UUIDs = [];
     sponsorLookupRetries = 0;
 
     //empty the preview bar
@@ -627,7 +627,6 @@ function skipToTime(v, index, sponsorTimes, openNotice) {
                 vote(1, currentUUID, null);
             }
         }
-    }
 
         //send telemetry that a this sponsor was skipped
         if (Config.config.trackViewCount && !sponsorSkipped[index]) {
@@ -641,6 +640,7 @@ function skipToTime(v, index, sponsorTimes, openNotice) {
             }
         }
     }
+}
 
 function unskipSponsorTime(UUID) {
     if (sponsorTimes != null) {