Chrome version : 51.0.2701.0 (Official Build) 5d32c4d7ac9cd3e4a45a5cc1fc547103b66816c7-refs/heads/master@{#385337} 32/64 bit
OS : Windows (Win 7 aero enabled), Linux

Precondition : In PrintPreview, set Destination to any Printer.

Steps : 
1. Launch chrome, open NTP and hit Ctrl+P.
2. Click inside 'Copies' text box, delete default value and put ' -1 ' in text box.
3. Now press Backspace twice and observe the text box.

Actual : After pressing backspace, two I-beam pointers are seen in textbox.
Expected : Instead, only one I-beam pointer should be seen in textbox.

This is a regression issue broken in 'M-51' and below is the manual regression and narrow bisect info.
Good Build :  51.0.2695.0
Bad Build :  51.0.2696.0

Narrow Bisect : 
https://chromium.googlesource.com/chromium/src/+log/8694d7b928ba2b7bfe73fbcb74d052faa5eb309c..4c9fd0d3128c87e1289e9ac1d47fec18d7107077?pretty=fuller&n=10000

Suspecting : r384377  from narrow bisect

@sky : Could you please help to reassign if your change is not the cause for this issue

Note : Above issue is not seen on Mac OS.
 

Deleted: Actual_pointer.mp4 628 KB

Actual_pointer.mp4 628 KB Download

Deleted: Expected_pointer.mp4 768 KB

Expected_pointer.mp4 768 KB Download