Avoid filegroup dependency from ICU to libcore.

The timezone_host_files filegroup was used to build the timezone-host
library in libcore. Since TzDataSetVersion.java in ICU depends on
libcore annotations and timezone-host doesn't add any libcore code that
depends on TzDataSetVersion.java, this topic reverses the dependency by
moving the timezone-host library to ICU. Libcore in the ART SDK instead
exports art.module.api.annotations that is needed to build
timezone-host.

Test: `m timezone-host` built entirely from sources and with
  art.module.api.annotations coming from the prebuilt produced by
  `build/soong/scripts/build-aml-prebuilts.sh art-module-host-exports`
Test: `m art-module-host-exports` on master-art (no ICU sources)
Bug: 172480615
Change-Id: Id7af8c859c0ddd2c06a200d07b8d039d9a754459
1 file changed