Use and export proguard flags from static dependencies

Export proguard flags from Android library modules, and use them
from static dependencies in Android apps when running proguard.
Also export them to Make.

Unlike Make, which concatentates all the exported flags from
dependencies, Soong dedups exported flags files.

Bug: 73724997
Test: m checkbuild
Change-Id: I8f86fecb09cbc591832ce67e8ecef551a6600349
Merged-In: I8f86fecb09cbc591832ce67e8ecef551a6600349
(cherry picked from commit 89c31581a52e4534e1a726f49d700250d676e1a2)

3 files changed, 36 insertions, 3 deletions

diff --git a/java/aar.go b/java/aar.go
index 16d82af4..47676fd9 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -25,6 +25,7 @@ import (
 type AndroidLibraryDependency interface {
 	Dependency
 	ExportPackage() android.Path
+	ExportedProguardFlagFiles() android.Paths
 }
 
 func init() {
@@ -247,6 +248,12 @@ type AndroidLibrary struct {
 	androidLibraryProperties androidLibraryProperties
 
 	aarFile android.WritablePath
+
+	exportedProguardFlagFiles android.Paths
+}
+
+func (a *AndroidLibrary) ExportedProguardFlagFiles() android.Paths {
+	return a.exportedProguardFlagFiles
 }
 
 var _ AndroidLibraryDependency = (*AndroidLibrary)(nil)
@@ -279,6 +286,14 @@ func (a *AndroidLibrary) GenerateAndroidBuildActions(ctx android.ModuleContext)
 		BuildAAR(ctx, a.aarFile, a.outputFile, a.manifestPath, a.rTxt, res)
 		ctx.CheckbuildFile(a.aarFile)
 	}
+
+	ctx.VisitDirectDeps(func(m android.Module) {
+		if lib, ok := m.(AndroidLibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
+			a.exportedProguardFlagFiles = append(a.exportedProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
+		}
+	})
+
+	a.exportedProguardFlagFiles = android.FirstUniquePaths(a.exportedProguardFlagFiles)
 }
 
 func AndroidLibraryFactory() android.Module {
@@ -327,6 +342,10 @@ func (a *AARImport) ExportPackage() android.Path {
 	return a.exportPackage
 }
 
+func (a *AARImport) ExportedProguardFlagFiles() android.Paths {
+	return android.Paths{a.proguardFlags}
+}
+
 func (a *AARImport) Prebuilt() *android.Prebuilt {
 	return &a.prebuilt
 }
diff --git a/java/androidmk.go b/java/androidmk.go
index 8b9de789..92b9457e 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -233,7 +233,8 @@ func (a *AndroidLibrary) AndroidMk() android.AndroidMkData {
 
 		fmt.Fprintln(w, "LOCAL_SOONG_RESOURCE_EXPORT_PACKAGE :=", a.exportPackage.String())
 		fmt.Fprintln(w, "LOCAL_FULL_MANIFEST_FILE :=", a.manifestPath.String())
-		fmt.Fprintln(w, "LOCAL_SOONG_EXPORT_PROGUARD_FLAGS :=", a.proguardOptionsFile.String())
+		fmt.Fprintln(w, "LOCAL_SOONG_EXPORT_PROGUARD_FLAGS :=",
+			strings.Join(a.exportedProguardFlagFiles.Strings(), " "))
 		fmt.Fprintln(w, "LOCAL_UNINSTALLABLE_MODULE := true")
 		fmt.Fprintln(w, "LOCAL_DEX_PREOPT := false")
 	})
diff --git a/java/app.go b/java/app.go
index dd83a0a7..1fdce129 100644
--- a/java/app.go
+++ b/java/app.go
@@ -63,6 +63,10 @@ type AndroidApp struct {
 	appProperties appProperties
 }
 
+func (a *AndroidApp) ExportedProguardFlagFiles() android.Paths {
+	return nil
+}
+
 var _ AndroidLibraryDependency = (*AndroidApp)(nil)
 
 type certificate struct {
@@ -116,8 +120,17 @@ func (a *AndroidApp) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	// apps manifests are handled by aapt, don't let Module see them
 	a.properties.Manifest = nil
 
-	a.Module.extraProguardFlagFiles = append(a.Module.extraProguardFlagFiles,
-		a.proguardOptionsFile)
+	var staticLibProguardFlagFiles android.Paths
+	ctx.VisitDirectDeps(func(m android.Module) {
+		if lib, ok := m.(AndroidLibraryDependency); ok && ctx.OtherModuleDependencyTag(m) == staticLibTag {
+			staticLibProguardFlagFiles = append(staticLibProguardFlagFiles, lib.ExportedProguardFlagFiles()...)
+		}
+	})
+
+	staticLibProguardFlagFiles = android.FirstUniquePaths(staticLibProguardFlagFiles)
+
+	a.Module.extraProguardFlagFiles = append(a.Module.extraProguardFlagFiles, staticLibProguardFlagFiles...)
+	a.Module.extraProguardFlagFiles = append(a.Module.extraProguardFlagFiles, a.proguardOptionsFile)
 
 	if ctx.ModuleName() != "framework-res" {
 		a.Module.compile(ctx, a.aaptSrcJar)