Generate linker config with packaged items.

Previously, we gather all deps without checking if a dep is actually one
of packaged items (CopyDepsToZip contents)

For example, following items shouldn't be listed.

provideLibs: "platform-mainline-sdk_libartpalette-system@current.so"
provideLibs: "platform-mainline-sdk_liblog@current.so"
provideLibs: "runtime-module-sdk_libc@current.so"
provideLibs: "runtime-module-sdk_libdl@current.so"
provideLibs: "runtime-module-sdk_libdl_android@current.so"
provideLibs: "runtime-module-sdk_libm@current.so"

Now, we gather only those modules contributing CopyDepsToZip to generate
linker config for android_system_image.

Test: m nothing
Test: m microdroid
Test: conv_linker_config print -s
    .../microdroid/android_common/root/system/etc/linker.config.pb
    shouldn't list sdk members.
Change-Id: Ife5d2193ab59970367d10e196aaaa922c6582862

android/packaging.go

@@ -198,8 +198,8 @@ func (p *PackagingBase) AddDeps(ctx BottomUpMutatorContext, depTag blueprint.Dep
 	}
 }
 
-// See PackageModule.CopyDepsToZip
+// Returns transitive PackagingSpecs from deps
-func (p *PackagingBase) CopyDepsToZip(ctx ModuleContext, zipOut WritablePath) (entries []string) {
+func (p *PackagingBase) GatherPackagingSpecs(ctx ModuleContext) map[string]PackagingSpec {
 	m := make(map[string]PackagingSpec)
 	ctx.VisitDirectDeps(func(child Module) {
 		if pi, ok := ctx.OtherModuleDependencyTag(child).(PackagingItem); !ok || !pi.IsPackagingItem() {
@@ -211,7 +211,12 @@ func (p *PackagingBase) CopyDepsToZip(ctx ModuleContext, zipOut WritablePath) (e
 			}
 		}
 	})
+	return m
+}
 
+// See PackageModule.CopyDepsToZip
+func (p *PackagingBase) CopyDepsToZip(ctx ModuleContext, zipOut WritablePath) (entries []string) {
+	m := p.GatherPackagingSpecs(ctx)
 	builder := NewRuleBuilder(pctx, ctx)
 
 	dir := PathForModuleOut(ctx, ".zip")

filesystem/system_image.go

@@ -50,17 +50,19 @@ func (s *systemImage) buildExtraFiles(ctx android.ModuleContext, root android.Ou
 func (s *systemImage) buildLinkerConfigFile(ctx android.ModuleContext, root android.OutputPath) android.OutputPath {
 	input := android.PathForModuleSrc(ctx, android.String(s.properties.Linker_config_src))
 	output := root.Join(ctx, "system", "etc", "linker.config.pb")
+
+	// we need "Module"s for packaging items
 	var otherModules []android.Module
+	deps := s.GatherPackagingSpecs(ctx)
 	ctx.WalkDeps(func(child, parent android.Module) bool {
-		// Don't track direct dependencies that aren't not packaged
+		for _, ps := range child.PackagingSpecs() {
-		if parent == s {
+			if _, ok := deps[ps.RelPathInPackage()]; ok {
-			if pi, ok := ctx.OtherModuleDependencyTag(child).(android.PackagingItem); !ok || !pi.IsPackagingItem() {
-				return false
-			}
-		}
 				otherModules = append(otherModules, child)
+			}
+		}
 		return true
 	})
+
 	builder := android.NewRuleBuilder(pctx, ctx)
 	linkerconfig.BuildLinkerConfig(ctx, builder, input, otherModules, output)
 	builder.Build("conv_linker_config", "Generate linker config protobuf "+output.String())