In the context of incremental soong, the output files
inter-module-communication will be through OutputFilesProvider.
The OutputFileProducer interface will be deprecated.
This CL also removes the unused field "intermediatePath" from
build_flag_declarations and aconfig_declarations
Test: CI
Bug: 339477385
Change-Id: I8417db7ca6ece50b3ecd807fc3b6356aa52b18e0
Define release_flags_json module type to install build_flags.json in
'etc'. release_flags_json reads the json files generated from the
soong release-config command.
Bug: 324996303
Test: build and see if the files are installed
Change-Id: I8cdcb7c61dd75cc54e4912d2ed7d1687f424151c
