Enforce a minimum width and height of 1 in GlyphMetric::SetSize(),
preventing X11SalGraphics::GetGlyphBoundRect() from returning a
Rectangle that has one side set as RECT_EMPTY.

This problem has surfaced due to the change of the status bar in
ce14342c, causing the
AccessibleStatusBarItem to fail in getCharacterBounds() because
the text of the control, "Words: 0", now contains a space, for which an
empty Rectangle bounding box is created, which results in a wrong
return value from getCharacterBounds():

LOG> Character bounds outside component
LOG> Character rect: 43, -566, 0, 0
LOG> Component rect: 91, 2, 71, 18

It turns out that the following test was disabled due to this problem,
so re-enable it now:
toolkit.AccessibleFixedText::com::sun::star::accessibility::XAccessibleText