Use a partition packaging spec filter for android_filesystem

This revives https://r.android.com/3308803. The use case for this filter
is
1. To remove the transitive shared library dependencies of `system_ext`
   binaries that are intended to be installed in `system`. Without this
   filter, we get two copies of libc.so, libz.so, ... on device
2. To filter out dexpreopt files of apps. Even if an app is installed in
   `/system_ext`, its dexpreopt files will be installed in
   `system_other`. Kati allows this by allowing ctx.InstallFile to
   specify the path relative to device root.

Diff in autogenerated `system_ext` partition for aosp cf before and
after this CL https://diff.googleplex.com/#key=6ekb09PtreNh

Test: go test ./filesystem
Bug: 372487849
Change-Id: Ie52723be2469d3b210ee1ebb62997d378d44788b

1 files changed, 25 insertions, 0 deletions

diff --git a/filesystem/filesystem_test.go b/filesystem/filesystem_test.go
index 057dcaaff..1e508364c 100644
--- a/filesystem/filesystem_test.go
+++ b/filesystem/filesystem_test.go
@@ -584,3 +584,28 @@ func TestErofsPartition(t *testing.T) {
 	android.AssertStringDoesContain(t, "erofs fs type compress hint", buildImageConfig, "erofs_default_compress_hints=compress_hints.txt")
 	android.AssertStringDoesContain(t, "erofs fs type sparse", buildImageConfig, "erofs_sparse_flag=-s")
 }
+
+// If a system_ext/ module depends on system/ module, the dependency should *not*
+// be installed in system_ext/
+func TestDoNotPackageCrossPartitionDependencies(t *testing.T) {
+	result := fixture.RunTestWithBp(t, `
+		android_filesystem {
+			name: "myfilesystem",
+			deps: ["binfoo"],
+			partition_type: "system_ext",
+		}
+
+		cc_binary {
+			name: "binfoo",
+			shared_libs: ["libfoo"],
+			system_ext_specific: true,
+		}
+		cc_library_shared {
+			name: "libfoo", // installed in system/
+		}
+	`)
+
+	partition := result.ModuleForTests("myfilesystem", "android_common")
+	fileList := android.ContentFromFileRuleForTests(t, result.TestContext, partition.Output("fileList"))
+	android.AssertDeepEquals(t, "filesystem with dependencies on different partition", "bin/binfoo\n", fileList)
+}