function writeCues() {
                var
                    ebml = {
                        "id": 0x1C53BB6B,
                        "data": cues
                    },
                    
                    cuesBuffer = new ArrayBufferDataStream(16 + cues.length * 32); // Pretty crude estimate of the buffer size we'll need
                
                writeEBML(cuesBuffer, blobBuffer.pos, ebml);
                blobBuffer.write(cuesBuffer.getAsDataArray());
                
                // Now we know where the Cues element has ended up, we can update the SeekHead
                seekPoints.Cues.positionEBML.data = fileOffsetToSegmentRelative(ebml.offset);
            }
Write a Cues element to the blobStream using the global `cues` array of CuePoints (use addCuePoint()).
The seek entry for the Cues in the SeekHead is updated.