Chrome Version: 56.0.2924.21 (Official Build)4d0fd85f092f947ef72046f62e953ecf44d5e64a-refs/branch-heads/2924@{#401} 32/64-bit.
OS: Windows (7,8,8.1,10), Linux(14.04 LTS)

Steps:
1. Launch chrome and navigate to chrome://md-settings
2. Press Ctrl+Shift+I to open devtools and toggle to device mode.
3. Select 'iPhone 6 Plus' and click on any of the drop down menu.

Actual: Border of the drop down menu is not proper (Unwanted black lines seen on two sides of drop down).

Expected: Border of the drop down menu should be proper.

This is a non-regression issue seen from M-55, build no. 55.0.2882.4 (new drop down menus is seen from this build.)

Note: Issue is not seen in Mac OS.

 

Deleted: Actual.png 227 KB

	Actual.png 227 KB View Download

Deleted: Expected.png 232 KB

	Expected.png 232 KB View Download