add on for upload task and storage error

Author: michaelprichardson

firebase-common/src/jsMain/kotlin/dev/gitlive/firebase/externals.kt

@@ -588,6 +588,7 @@ external object firebase {
             fun cancel(): Boolean
             fun pause(): Boolean
             fun resume(): Boolean
+            fun on(event: String, next: (snapshot: UploadTaskSnapshot) -> Unit, error: (a: FirebaseStorageError) -> Unit, complete: () -> Unit): () -> Unit
         }
 
         open class UploadTaskSnapshot {
@@ -599,6 +600,13 @@ external object firebase {
             val totalBytes: Number
         }
 
+        open class FirebaseStorageError {
+            val code: String
+            val message: String
+            val name: String
+            val stack: String?
+        }
+
     }
 
     fun remoteConfig(app: App? = definedExternally): remoteConfig.RemoteConfig