I added two more patches.

The first simply adds native methods for using hildon buttons and file dialog chooser and (most important) cleans a little bit up the code.
I.e. the methods flagged with "no_gen" have been moved into os_custom.c. This should improve the maintainability.

The second patch changes org.eclipse.swt.widgets.FileDialog to make use of HildonFileChooserDialog.

Again the patches are in the usual place and a compiled version has been uploaded to experimental.