JS lib: added missed arguments to Blob constructor.

#KT-6654 Fixed

js/js.libraries/src/html5/files.kt

@@ -25,7 +25,7 @@ public class File() : Blob() {
 }
 
 native
-public open class Blob() {
+public open class Blob(blobParts: Array<Any>? = undefined, options: BlobPropertyBag? = undefined) {
     public val size: Int = noImpl
     public val type: String = noImpl
     //Blob slice(optional long long start,
@@ -33,3 +33,8 @@ public open class Blob() {
     //optional DOMString contentType);
     //
 }
+
+native
+public trait BlobPropertyBag {
+    public val type: String
+}