ChromeOS:
73.0.3669.42(Platform 11578.0.0-19.01.13) kevin test
Input tools version: 73.0.20181227.227100664

Steps:
1.Switch to US keyboard.
2.Open US settings, Enable swipe gestures 
"Swipe from the edges of the keyboard to move the cursor, or from the backspace key to delete whole words.“
3.Type something.
4.Swipe from the edges of the keyboard.
5.Long press the backspace key.

Actual:
4.No any response.
5.Just delete letters while press the backspace key.