Changes to installed app details screen for instant apps

Bug: 35098444
Test: make RunSettingsRoboTests

This implements the following changes to the app details screen:

-Suppresses the "Uninstall" and "Force Stop" buttons
-Adds "Install app" and "Clear app" buttons
-Adds a mechanism for showing a link to the store's app details
 page that can be different from the default for installed apps.

Change-Id: Icea83f7d1fde62d4101cb0c8a6d03849f6c56bca