Introduce Font and its builder class

This CL is a ground work of the new Typeface construction API and
nobody uses this class except for CTS.
I'll add FontFamily class to be able to bundle these Font clases
and register to the Typeface.

Bug: 72665240
Test: atest FontTest
Test: atest CtsWidgetTestCases:EditTextTest
    CtsWidgetTestCases:TextViewFadingEdgeTest
    FrameworksCoreTests:TextViewFallbackLineSpacingTest
    FrameworksCoreTests:TextViewTest FrameworksCoreTests:TypefaceTest
    CtsGraphicsTestCases:TypefaceTest CtsWidgetTestCases:TextViewTest
    CtsTextTestCases FrameworksCoreTests:android.text
    CtsWidgetTestCases:TextViewPrecomputedTextTest

Change-Id: I68555a8b4bd6dd770ba7baae72d9a3777b2087a5