fix silent init file write failure

Reviewed-on: #11

package/ios/Core/ChunkedRecorder.swift

@@ -56,14 +56,15 @@ extension ChunkedRecorder: AVAssetWriterDelegate {
 
   private func saveInitSegment(_ data: Data) {
     let url = outputURL.appendingPathComponent("init.mp4")
-    save(data: data, url: url)
+    if save(data: data, url: url) {
       onChunkReady(url: url, type: .initialization)
     }
+  }
 
   private func saveSegment(_ data: Data, report: AVAssetSegmentReport?) {
     let name = "\(chunkIndex).mp4"
     let url = outputURL.appendingPathComponent(name)
-    save(data: data, url: url)
+    if save(data: data, url: url) {
       let duration = report?
         .trackReports
         .filter { $0.mediaType == .video }
@@ -72,12 +73,15 @@ extension ChunkedRecorder: AVAssetWriterDelegate {
       onChunkReady(url: url, type: .data(index: chunkIndex, duration: duration))
       chunkIndex += 1
     }
+  }
 
-  private func save(data: Data, url: URL) {
+  private func save(data: Data, url: URL) -> Bool {
     do {
       try data.write(to: url)
+      return true
     } catch {
       ReactLogger.log(level: .error, message: "Unable to write \(url): \(error.localizedDescription)")
+      return false
     }
   }