Example URL:
naver.com

Steps to reproduce the problem:
1. Enable talkback from accessibility settings. 
2. Fetch naver.com and scroll the page to bottom.
3. Click on the page up button present in the bottom right corner of the screen.
4. Now that the button is focused with a blue rect, scroll the page again. 

What is the expected behavior?
The blue rect (focus) for the button should not move i.e should stay with the button which is fixed.

What went wrong?
The blue focus rect moves with page while scrolling

Does it occur on multiple sites: Yes

Is it a problem with a plugin? N/A 

Did this work before? N/A 

Does this work in other browsers? N/A 

Chrome version: 51.0.2704.81  Channel: n/a
OS Version: Android L
Flash Version: 

The issue is observed for all fixed elements. Browser doesn't understand fixed elements in talkback mode and as a result when fixed elements are focused and then moved, the focus rect moves along with the scroll.