Add UI updates for incremental app installs.

1. Changed Preload Icon UI to be grayscale while the app is not startable.
2. Added progress bar for when app is installed but still ownloading.
3. Updated Preload Icon progress and click handling to use new incremental api.

Progress bar color updates will follow in a separate CL.

Demo: https://drive.google.com/file/d/1H1EvtTorLeJwC1eiq10tm-TT81YZ6osk/view?usp=sharing

Bug: 171008815

Test: manual

Change-Id: I5874a5146d79a8c91d7d90ff0b9c1c427a3c95dd
24 files changed