[PIP2] Enable rounded corners

Enables PIP rounded corners and shadow radius for teamfood.

Flag: com.android.wm.shell.enable_pip2
Bug: 378913217
Test: Manually check CUJs for Youtube and Maps
Test: atest WMShellUnitTests:PipEnterAnimatorTest
Test: atest WMShellUnitTests:PipResizeAnimatorTest
Change-Id: I19c8d62e8193b411b96703cc2f4472482eaec028