Dedupe logic to generate linker.config.pb

Between android_filesystem and generic_system_image.
`getLibsForLinkerConfig` will return a list of provideLibs and
requireLibs for the fileystem. `linkerConfig.BuildLinkerConfig` will
then filer out the non-stub libraries.

For `android_filesystem`, requireLibs is ignored for now to match the
logic in the kati built vendor.img

Test: m nothing --no-skip-soong-tests
Test: no diff in out/soong/.intermediates/build/make/target/product/generic/generic_system_image/android_common/gen/root-extra/system/etc/linker.config.pb
paste of cmd: https://diff.googleplex.com/#key=KAqqP9bhKZMD

Change-Id: I1f1d626a3a161fb2e12597909fd287533cbb8482

1 files changed, 6 insertions, 3 deletions

diff --git a/filesystem/filesystem_test.go b/filesystem/filesystem_test.go
index cb27f6464..8fe5daca0 100644
--- a/filesystem/filesystem_test.go
+++ b/filesystem/filesystem_test.go
@@ -670,18 +670,21 @@ func TestInstallLinkerConfigFile(t *testing.T) {
 android_filesystem {
     name: "myfilesystem",
     deps: ["libfoo_has_no_stubs", "libfoo_has_stubs"],
-    linker_config_srcs: ["linker.config.json"]
+    linker_config_srcs: ["linker.config.json"],
+    partition_type: "vendor",
 }
 cc_library {
     name: "libfoo_has_no_stubs",
+    vendor: true,
 }
 cc_library {
     name: "libfoo_has_stubs",
     stubs: {symbol_file: "libfoo.map.txt"},
+    vendor: true,
 }
 	`)
 
 	linkerConfigCmd := result.ModuleForTests("myfilesystem", "android_common").Rule("build_filesystem_image").RuleParams.Command
-	android.AssertStringDoesContain(t, "", linkerConfigCmd, "conv_linker_config proto --force -s linker.config.json")
-	android.AssertStringDoesContain(t, "", linkerConfigCmd, "--key provideLibs --value libfoo_has_stubs.so")
+	android.AssertStringDoesContain(t, "Could not find linker.config.json file in cmd", linkerConfigCmd, "conv_linker_config proto --force -s linker.config.json")
+	android.AssertStringDoesContain(t, "Could not find stub in `provideLibs`", linkerConfigCmd, "--key provideLibs --value libfoo_has_stubs.so")
 }