Use SystemUI theme to inflate FrameLayout and SplashScreenView

The FrameLayout and SplashScreenView are only used as container in
StartingSurfaceDrawer, so they do not need to be inflated by app's
context, which could be affected by app's resources.

Bug: 197936273
Test: cold launch test app and show splash screen.
Test: launch several apps to verify that everything is fine.
Test: atest StartingSurfaceDrawerTests
Change-Id: I6de444546b5dfba23fc1d7c9c4deb12787d667c5