Adds a serialize helper function to native table (#6059)

* Adds a serialize helper function to native table
* Updated version

swift/Sources/FlatBuffers/FlatBufferObject.swift

@@ -6,8 +6,6 @@ public protocol FlatBufferObject {
     init(_ bb: ByteBuffer, o: Int32)
 }
 
-public protocol NativeTable {}
-
 public protocol ObjectAPI {
     associatedtype T
     static func pack(_ builder: inout FlatBufferBuilder, obj: inout T) -> Offset<UOffset>

swift/Sources/FlatBuffers/NativeTable.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+public protocol NativeTable {}
+
+extension NativeTable {
+    
+    /// Serialize is a helper function that serailizes the data from the Object API to a bytebuffer directly th
+    /// - Parameter type: Type of the Flatbuffer object
+    /// - Returns: returns the encoded sized ByteBuffer
+    public func serialize<T: ObjectAPI>(type: T.Type) -> ByteBuffer where T.T == Self {
+        var builder = FlatBufferBuilder(initialSize: 1024)
+        return serialize(builder: &builder, type: type.self)
+    }
+    
+    /// Serialize is a helper function that serailizes the data from the Object API to a bytebuffer directly.
+    ///
+    /// - Parameters:
+    ///   - builder: A FlatBufferBuilder
+    ///   - type: Type of the Flatbuffer object
+    /// - Returns: returns the encoded sized ByteBuffer
+    /// - Note: The `serialize(builder:type)` can be considered as a function that allows you to create smaller builder instead of the default `1024`.
+    ///  It can be considered less expensive in terms of memory allocation
+    public func serialize<T: ObjectAPI>(builder: inout FlatBufferBuilder, type: T.Type) -> ByteBuffer where T.T == Self {
+        var s = self
+        let root = type.pack(&builder, obj: &s)
+        builder.finish(offset: root)
+        return builder.sizedBuffer
+    }
+}