The combobox test with a height of 3 doesn't work well -- it is difficult
to tell exactly what the issues are when the scrollbar handle is that small.

I changed the -height to 5 in the test script.
It is much better.

With a -height of 5 in the test script, it still seems that the very
top and very bottom of the handle will not allow a grab.

With a -height of 3 in the test, this translates to being
extremely difficult to grab the handle.

With a -height of 10 in the test, the scrollbar handle is a good size
and it works very well.  I cannot duplicate any issues in this case.

So in any situation where the handle is sized very small due to height
vs. number of rows in the scroll area, it will still be an issue.


Warnings:

warning: excess
      elements in scalar initializer
    {15, 54, 26, 14, 14, kControlSizeNormal}, /* kThemeScrollBarMedium */
         ^~
warning: unused
      variable 'variant' [-Wunused-variable]
    int variant, fieldLength;
        ^
warning: unused
      variable 'variant' [-Wunused-variable]
    int variant;
        ^
3 warnings generated.