Add healthfitness sources to framework-doc-system-stubs.

This will allow us to use the HealthFitness APIs across the framework,
most immediately for permissions.

Bug: 378992337
Change-Id: Iccd7c8efdff68e7d26d8f16d02ab361788cd6fda
Flag: EXEMPT DOCS_ONLY
Test: m framework-doc-system-stubs
1 file changed