DownloadNotifier: Standardize play store and browser downloads

Image: http://i.imgur.com/w3VaRUK.png

PS1: Initial commit
PS2: Standardize all things!

Change-Id: I5e6c5def7dae10d714fd180693e95bc61205a57b
Merge "DownloadNotifier: Standardize play store and browser downloads" into kk4.4