tmf: Fix alignment SWTBot test at low resolution

tmf: Fix alignment SWTBot test at low resolution

The test now runs at 640x480.

Make sure the views have enough space otherwise they might not be
painted at all and they won't react to the sash being dragged.

Change-Id: Ib7feb329e9d2fe99fc5ecf02dba122b8324eb950
Signed-off-by: Marc-Andre Laperle <marc-andre.laperle@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/60553
Reviewed-by: Hudson CI
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>