Vertical stretching arrows in table cells can cause extra space between rows

[dpvc]

This example shows too much space between the A and the arrow:

<math display="block">
<mtable>
<mtr><mtd><mi>A</mi></mtd></mtr>
<mtr><mtd><mo stretchy="true" minsize="2em">&#x2193;</mo></mtd></mtr>
</mtable>
</math>

It turns out that the mtable.js code has a wrong index when recording the height and depth of the row when a cell contains a single stretchy (embellished) operator, so it sets the height and depth of the wrong row (in this case, the top row rather than the bottom row).

[dpvc]

The issue468 branch of my fork of MathJax contains the fix.

[dpvc]

=> Merged

[fred-wang]

MathMLToDisplay/issue468.html

=> In Testsuite

[pkra]

Can be closed now that it's pushed everywhere?

[dpvc]

I had left it open because Fred had it marked to create a test for it. Now that that's done, we can close it.