[Reland] Cache the variation instance of Typeface

This is a reland of the 4cefdc6d

The previous attempt breaks robolectric tests of settings but it
needs to be fix-forward. Context: b/358347869

Performance numbers on Pixel 8 Pro.

Non-Cached: 366,835 ns
    Cached:   2,427 ns

Bug: 355462362
Test: PaintTest
Flag: com.android.text.flags.typeface_cache_for_var_settings
Change-Id: I0f1e253eae5e2774ef4f10dcf5d0c8e8fbe6e367