Introduce createCollectionWithVariation.

This is 2nd attempt of I08e9b74192f8af1d045f1276498fa4e60d73863e.
The original CL was reverted due to conflicting with another CL submitted
before.

Here is the original commit message of reverted change.

This lays the groundwork for variation settings support.
Since we should regard different variations of a font as different fonts, we
need to create new typefaces. To reuse the same instance of MinikinFont, as
much as possible, FontFamily::createFamilyWithVariation now reuses an
existence instance, while incrementing the reference count.

Test: minikin_tests
Bug: 33062398
Change-Id: Ib25bf1bb5a5191e15a6523954146521464c91906

• include/minikin/FontCollection.h[diff]
• include/minikin/FontFamily.h[diff]
• include/minikin/MinikinFont.h[diff]
• libs/minikin/AnalyzeStyle.cpp[Deleted - diff]
• libs/minikin/Android.mk[diff]
• libs/minikin/FontCollection.cpp[diff]
• libs/minikin/FontFamily.cpp[diff]
• libs/minikin/FontUtils.cpp[Added - diff]
• libs/minikin/FontUtils.h[Renamed from include/minikin/AnalyzeStyle.h - diff]
• tests/data/MultiAxis.ttf[Added - diff]
• tests/data/MultiAxis.ttx[Added - diff]
• tests/unittest/Android.mk[diff]
• tests/unittest/FontCollectionTest.cpp[diff]
• tests/unittest/FontFamilyTest.cpp[diff]
• tests/util/MinikinFontForTest.cpp[diff]
• tests/util/MinikinFontForTest.h[diff]