Change package used for adapting layout to window size

androidx.window.core.layout.WindowSizeClass is planned to replace
androidx.compose.material3.windowsizeclass.WindowSizeClass that's used
in SysUI for adapting layout to window size.

This CL changes usage of androidx.compose.material3.windowsizeclass
.WindowSizeClass to androidx.window.core.layout.WindowSizeClass
across SystemUI code while preserving the original logic.

Added benefit of using androidx.window.core.layout.WindowSizeClass
is the avaialability of Large (1200 dp) and Extra-large (1600 dp) width
breakpoints.

Test: existing tests for appropriate features
Flag: EXEMPT PURE_REFACTOR
Bug: 441954375

Change-Id: I701826cc37ea4ef973b2d420da029ff05845fb8f