
Adds an aria-label to added and removed rows marking the row as "added" or "removed" for screen readers. As part of this change, the <tr> elements that make up the diff are now focusable. Test plan: - Somewhat included as a part of testing this functionality is the use of WCT's a11ySuite function[1]. This will be introduced in a later change. [1] https://goo.gl/P15eE6 Bug: Issue 6435 Change-Id: I676fc171d404ca6e8e9276965192b1452595fa61