Fix clickedTime on rows when Timeline has horizontal padding

[marklawlor]

Proposed Change:

The clicked time is incorrect when horizontal padding is applied to the timeline.

It now calculates based upon the row screen X position, instead of the width of the sidebar

Change type

• [x] Bugfix
• [ ] New feature

Checklist

• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have added necessary documentation (if appropriate)