Merge pull request #3117 from kapodamy/fixup

fixup for #3081

app/src/main/java/org/schabi/newpipe/streams/Mp4FromDashWriter.java

@@ -291,7 +291,9 @@ public class Mp4FromDashWriter {
                 sampleCount[i] = 1;// the index is not base zero
                 sampleExtra[i] = -1;
             }
-            writeEntryArray(tablesInfo[i].sbgp, 1, sampleCount[i]);
+            if (tablesInfo[i].sbgp > 0) {
+                writeEntryArray(tablesInfo[i].sbgp, 1, sampleCount[i]);
+            }
         }
 
         if (auxBuffer == null) {