Fixed some css selectors that broke when Visualizer DOM changed.

Recently some changes were made to Web Visualizer that resulted in
new class names being put on elements this test needed to interact
with.  I changed the css selectors to reflect the new class names.

Change-Id: I774479563ded518c980c5f7ec1f9f9dc3dfb6521
Merge topic 'pvweb-fix-visualizer-can-test' into next

cc19756 Fixed some css selectors that broke when Visualizer DOM changed.