Unhandled exception on cutting text without selecting when using text tool

[supershadoe]

Pinta version 2.0.1 on Arch Linux

When Ctrl+x is pressed with the text tool active, with empty text or some text entered(without finalizing) and without selecting the text, an exception is raised by the app.

Exception details:
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.ArgumentException: Invalid start position (Parameter 'start')
   at Pinta.Core.TextEngine.DeleteText(TextPosition start, TextPosition end)
   at Pinta.Core.TextEngine.DeleteSelection()
   at Pinta.Core.TextEngine.PerformCut(Clipboard clipboard)
   at Pinta.Tools.TextTool.OnHandleCut(Document document, Clipboard cb)
   at Pinta.Core.BaseTool.DoHandleCut(Document document, Clipboard clipboard)
   at Pinta.Core.EditActions.HandlerPintaCoreActionsEditCutActivated(Object sender, EventArgs e)
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Span`1& arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.Delegate.DynamicInvokeImpl(Object[] args)
   at GLib.Signal.ClosureInvokedCB(Object o, ClosureInvokedArgs args)
   at GLib.SignalClosure.MarshalCallback(IntPtr raw_closure, IntPtr return_val, UInt32 n_param_vals, IntPtr param_values, IntPtr invocation_hint, IntPtr marshal_data)

[supershadoe (supershadoe)]

I think the issue is that there is no check to see if there is any text selected in PerformCut(); For the copying text part, PerformCopy() performs that check but DeleteSelection() is called with no check.

So, I think adding that one line for check is enough

[supershadoe (supershadoe)]

Also, I made a pull request fixing this small bug: https://github.com/PintaProject/Pinta/pull/219