Add virtual preload bit to ApplicationInfo

Change-Id: I2735b3823a8709b2ffb65cc8085ffcd952d3e1f2
Fixes: 64205417
Test: Manual
Test: Create a sample app and install it as a normal app
Test: See that it returns 'false' for "isVirtualPreload"
Test: Create a sample app and install it as a virtual preload ["--preload"]
Test: See that it returns 'true' for "isVirtualPreload"
Test: Run sample apps after reboot and see they return the correct value