Fix jagged inset shadow in menu

Also, remove unneeded div and make menu text look more vertically
centered.
https://trello.com/card/menu-inset-shadow-is-not-pixel-perfect/5112b893d0cd43cb370062bd/31

Change-Id: I2e5241655f92b656812ac0ce2155de1cb0f0ad42
Increase left padding in search input

Makes the distance between input's border and text uniform.
Also, remove redundant CSS.

Change-Id: Id18c8a97681e6f0ed8aa4ebc4ff918144f41b3ae
Merge "Increase left padding in search input"
Merge "Fix jagged inset shadow in menu"