Dovetail refresh for PowerMenu

Layout changes for each item in the PowerMenu including backgrounds,
padding and icons. This is to mimic Wear Material styling.

Also includes an update to the string for Emergency SOS action.

Later we might want to put some of these attributes as general themes to
that other alert dialogs in the framework can use the same styling

https://screenshot.googleplex.com/7xStDFauRa7Wcka

BUG: 173529191
Change-Id: I4e844186fc903f5366f491d0a1865a6a52ecd0fc