Let launcher modify window corner radius

Test: Manualy launch an app
Test: Press home when activity is on top of the stack
Test: Quick scrub
Test: Swipe up on the home button, swipe down
Test: Tap on notification on the shade
Test: atest ActivityLaunchAnimatorTest
Bug: 111514493
Change-Id: Ib7e29e7e07bf2a245ff949373af700b319e273fc