Can't save PNG after rotating by one degree

[Pete Forsyth]

This is on Pinta 1.6 on Ubuntu Mate 18.10.

If I edit a PNG file, I can save it after most changes; but if I rotate it one degree, I often can't save it. I get the following error message:

"Unhandled exception: Exception has been thrown by the target of an invocation."

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ArgumentException: dst.Size != src.Size
  at Pinta.Core.BinaryPixelOp.Apply (Cairo.ImageSurface dst, Cairo.ImageSurface src) [0x00018] in <d07abe89b0c1405ca613eaf73991f472>:0
  at Pinta.Core.Document.GetFlattenedImage () [0x0005c] in <d07abe89b0c1405ca613eaf73991f472>:0
  at Pinta.Core.GdkPixbufFormat.Export (Pinta.Core.Document document, System.String fileName, Gtk.Window parent) [0x00001] in <d07abe89b0c1405ca613eaf73991f472>:0
  at Pinta.Actions.SaveDocumentImplmentationAction.SaveFile (Pinta.Core.Document document, System.String file, Pinta.Core.FormatDescriptor format, Gtk.Window parent) [0x000ef] in <1b3ff3457ff6412b96782de825379d42>:0
  at Pinta.Actions.SaveDocumentImplmentationAction.Activated (System.Object sender, Pinta.Core.DocumentCancelEventArgs e) [0x00062] in <1b3ff3457ff6412b96782de825379d42>:0
  at Pinta.Core.FileActions.RaiseSaveDocument (Pinta.Core.Document document, System.Boolean saveAs) [0x0001f] in <d07abe89b0c1405ca613eaf73991f472>:0
  at Pinta.Core.Document.Save (System.Boolean saveAs) [0x0000b] in <d07abe89b0c1405ca613eaf73991f472>:0
  at Pinta.Actions.SaveDocumentAction.Activated (System.Object sender, System.EventArgs e) [0x0000b] in <1b3ff3457ff6412b96782de825379d42>:0
  at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00038] in <8f2c484307284b51944a1a13a14c0266>:0
   --- End of inner exception stack trace ---
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00053] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.Delegate.DynamicInvokeImpl (System.Object[] args) [0x0010d] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) [0x0000b] in <8f2c484307284b51944a1a13a14c0266>:0
  at System.Delegate.DynamicInvoke (System.Object[] args) [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0
  at GLib.Signal.ClosureInvokedCB (System.Object o, GLib.ClosureInvokedArgs args) [0x0006d] in <5a439e0caae7469886e7119d9f6bc621>:0
  at GLib.SignalClosure.Invoke (GLib.ClosureInvokedArgs args) [0x0000c] in <5a439e0caae7469886e7119d9f6bc621>:0
  at GLib.SignalClosure.MarshalCallback (System.IntPtr raw_closure, System.IntPtr return_val, System.UInt32 n_param_vals, System.IntPtr param_values, System.IntPtr invocation_hint, System.IntPtr marshal_data) [0x0006c] in <5a439e0caae7469886e7119d9f6bc621>:0

[Cameron White (cameronwhite91)]

This was fixed by some of the rotate / zoom changes upcoming in v1.7 (https://github.com/PintaProject/Pinta/commit/60266d3b860d6e49dac48b0efc1d46822798d3c3)