1770 - Fix dropdown positon in data grid

[tmcconechy]

Explain the details for making this change. What existing problem does the pull request solve?

Adds fixes to the dropdown position in data grid

Related github/jira issue (required):
Fixes #1770

Steps necessary to review your pull request (required):

• go to http://localhost:4300/ids-data-grid/editable-lookup.html
• in the last column open the dropdown and it should be positioned correctly
• try this in each row height
• try zooming
• also try dragging columns and make sure they line up in each row height
• try sorting in each row height and make sure the icons look ok

Included in this Pull Request:

• A test for the bug or feature.
• A note to the change log.