Add layout test for table repainting.

When the background of the table row is changed we repaint the entire table.
This CL adds a layout test showing the issue.

BUG=357291

Review URL: https://codereview.chromium.org/214513008

git-svn-id: svn://svn.chromium.org/blink/trunk@170221 bbb929c8-8fbe-4397-9dbb-9b2b20218538