Fix of Issue #1993

I modified a single line of code which seemed to fix the problem with the context menu height not being adjusted properly.  It was properly calculated but then, when 'set' it wasn't adjusting the intended HTML element as expected.  As a result the menu height was too large and, when placed 'above' it became apparent.  Below are screenshots before/after.

Before:
![](https://cloud.githubusercontent.com/assets/126301/5517082/97449acc-88fd-11e4-903e-d3fec10dc755.png)

After:
![contextmenu](https://cloud.githubusercontent.com/assets/10273533/5540333/4b6d5794-8a90-11e4-9861-631612eb36e2.png)