Added fallback for IE interop key press.
Fixed container map not returning item or container properly.
Fixed MouseEventArgs.GetPosition.  Changed event args classes to create a readonly property descriptor.
Fixing issues with ItemsControl, ItemsContainerGenerator.  Changed a few event args properties to be read only property descriptors.  Added unit test for ItemsControl.
Deleting ignored file.
Fixed ItemContainerGenerator.GeneratorPositionFromIndex from variable name collision.