Resolve corner/shadow radius with WindowContext

This CL changes to resolve corner/shadow radius resources with a proper
context on every relayout like how mCaptionHeight is handled.
Otherwise, the stale radius unexpectedly can be carried over when a
window moves across displays with different DPIs.

Flag: com.android.window.flags.enable_dynamic_radius_computation_bugfix
Bug: 399630464
Test: DesktopModeWindowDecorationTests
Test: WindowDecorationTests
Change-Id: I807e2e0143959ec66d073538dc2bb7d45fd9261e