remove some usages of SavestateBinary() with the CloneSavestate() extension method

src/BizHawk.Client.Common/Api/Classes/MemorySaveStateApi.cs

@@ -18,7 +18,7 @@ namespace BizHawk.Client.Common
 		public string SaveCoreStateToMemory()
 		{
 			var guid = Guid.NewGuid();
-			_memorySavestates.Add(guid, (byte[]) StatableCore.SaveStateBinary().Clone());
+			_memorySavestates.Add(guid, StatableCore.CloneSavestate());
 			return guid.ToString();
 		}
 

src/BizHawk.Client.EmuHawk/tools/TAStudio/BookmarksBranchesBox.cs

@@ -175,7 +175,7 @@ namespace BizHawk.Client.EmuHawk
 			return new TasBranch
 			{
 				Frame = Tastudio.Emulator.Frame,
-				CoreData = (byte[])Tastudio.StatableEmulator.SaveStateBinary().Clone(),
+				CoreData = Tastudio.StatableEmulator.CloneSavestate(),
 				InputLog = Movie.GetLogEntries().Clone(),
 				CoreFrameBuffer = MainForm.MakeScreenshotImage(),
 				OSDFrameBuffer = MainForm.CaptureOSD(),