Comment 7 for bug 1446217

Thanks for the repo steps, here's the exception:

System.AccessViolationException occurred
  HResult=-2147467261
  Message=Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
  Source=Pinta.Core
  StackTrace:
       at Pinta.Core.GradientRenderer.ProcessGradientLine(Byte startAlpha, Byte endAlpha, Int32 y, Rectangle rect, ImageSurface surface, ColorBgra* src_data_ptr, Int32 src_width) in c:\Users\Jonathan\Documents\Visual Studio 2013\Projects\PintaPobst2\Pinta.Core\Classes\GradientRenderer.cs:line 216
  InnerException: