Refactor special handling of hidden API encoding for master-art

Instead of encoding the hidden API with an empty set of flags when the
monolithic flags are not available this simply disables encoding
altogether which should have the same behavior at runtime.

This change also removes the unused flags field in hiddenAPISingleton
which was set but never read.

Bug: 179354495
Test: m nothing
Change-Id: I32d5825e5271829993dd4e5be4d4ee1b22fa7b22

apex/apex_test.go

@@ -4542,7 +4542,12 @@ func TestPrebuiltExportDexImplementationJars(t *testing.T) {
 }
 
 func TestBootDexJarsFromSourcesAndPrebuilts(t *testing.T) {
-	preparer := java.FixtureConfigureBootJars("myapex:libfoo", "myapex:libbar")
+	preparer := android.GroupFixturePreparers(
+		java.FixtureConfigureBootJars("myapex:libfoo", "myapex:libbar"),
+		// Make sure that the frameworks/base/Android.bp file exists as otherwise hidden API encoding
+		// is disabled.
+		android.FixtureAddTextFile("frameworks/base/Android.bp", ""),
+	)
 
 	checkBootDexJarPath := func(t *testing.T, ctx *android.TestContext, stem string, bootDexJarPath string) {
 		t.Helper()

java/hiddenapi.go

@@ -92,6 +92,12 @@ func (h *hiddenAPI) initHiddenAPI(ctx android.BaseModuleContext, configurationNa
 
 	h.configurationName = configurationName
 
+	// If the frameworks/base directories does not exist and no prebuilt hidden API flag files have
+	// been configured then it is not possible to do hidden API encoding.
+	if !ctx.Config().FrameworksBaseDirExists(ctx) && ctx.Config().PrebuiltHiddenApiDir(ctx) == "" {
+		return
+	}
+
 	// It is important that hiddenapi information is only gathered for/from modules that are actually
 	// on the boot jars list because the runtime only enforces access to the hidden API for the
 	// bootclassloader. If information is gathered for modules not on the list then that will cause
@@ -303,11 +309,7 @@ func hiddenAPIEncodeDex(ctx android.ModuleContext, output android.WritablePath,
 	}
 
 	enforceHiddenApiFlagsToAllMembers := true
-	// If frameworks/base doesn't exist we must be building with the 'master-art' manifest.
-	// Disable assertion that all methods/fields have hidden API flags assigned.
-	if !ctx.Config().FrameworksBaseDirExists(ctx) {
-		enforceHiddenApiFlagsToAllMembers = false
-	}
+
 	// b/149353192: when a module is instrumented, jacoco adds synthetic members
 	// $jacocoData and $jacocoInit. Since they don't exist when building the hidden API flags,
 	// don't complain when we don't find hidden API flags for the synthetic members.

java/hiddenapi_singleton.go

@@ -117,7 +117,6 @@ func hiddenAPISingletonFactory() android.Singleton {
 }
 
 type hiddenAPISingleton struct {
-	flags android.Path
 }
 
 // hiddenAPI singleton rules
@@ -136,17 +135,10 @@ func (h *hiddenAPISingleton) GenerateBuildActions(ctx android.SingletonContext)
 	// consistency.
 
 	if ctx.Config().PrebuiltHiddenApiDir(ctx) != "" {
-		h.flags = prebuiltFlagsRule(ctx)
+		prebuiltFlagsRule(ctx)
 		prebuiltIndexRule(ctx)
 		return
 	}
-
-	// These rules depend on files located in frameworks/base, skip them if running in a tree that doesn't have them.
-	if ctx.Config().FrameworksBaseDirExists(ctx) {
-		h.flags = flagsRule(ctx)
-	} else {
-		h.flags = emptyFlagsRule(ctx)
-	}
 }
 
 // Checks to see whether the supplied module variant is in the list of boot jars.
@@ -187,7 +179,7 @@ func isModuleInConfiguredList(ctx android.BaseModuleContext, module android.Modu
 	return true
 }
 
-func prebuiltFlagsRule(ctx android.SingletonContext) android.Path {
+func prebuiltFlagsRule(ctx android.SingletonContext) {
 	outputPath := hiddenAPISingletonPaths(ctx).flags
 	inputPath := android.PathForSource(ctx, ctx.Config().PrebuiltHiddenApiDir(ctx), "hiddenapi-flags.csv")
 
@@ -196,8 +188,6 @@ func prebuiltFlagsRule(ctx android.SingletonContext) android.Path {
 		Output: outputPath,
 		Input:  inputPath,
 	})
-
-	return outputPath
 }
 
 func prebuiltIndexRule(ctx android.SingletonContext) {
@@ -211,28 +201,6 @@ func prebuiltIndexRule(ctx android.SingletonContext) {
 	})
 }
 
-// flagsRule is a placeholder that simply returns the location of the file, the generation of the
-// ninja rules is done in generateHiddenAPIBuildActions.
-func flagsRule(ctx android.SingletonContext) android.Path {
-	outputPath := hiddenAPISingletonPaths(ctx).flags
-	return outputPath
-}
-
-// emptyFlagsRule creates a rule to build an empty hiddenapi-flags.csv, which is needed by master-art-host builds that
-// have a partial manifest without frameworks/base but still need to build a boot image.
-func emptyFlagsRule(ctx android.SingletonContext) android.Path {
-	rule := android.NewRuleBuilder(pctx, ctx)
-
-	outputPath := hiddenAPISingletonPaths(ctx).flags
-
-	rule.Command().Text("rm").Flag("-f").Output(outputPath)
-	rule.Command().Text("touch").Output(outputPath)
-
-	rule.Build("emptyHiddenAPIFlagsFile", "empty hiddenapi flags")
-
-	return outputPath
-}
-
 // tempPathForRestat creates a path of the same type as the supplied type but with a name of
 // <path>.tmp.
 //

java/hiddenapi_singleton_test.go

@@ -60,10 +60,7 @@ func TestHiddenAPISingleton(t *testing.T) {
 }
 
 func TestHiddenAPISingletonWithSourceAndPrebuiltPreferredButNoDex(t *testing.T) {
-	expectedErrorMessage :=
-		"hiddenapi has determined that the source module \"foo\" should be ignored as it has been" +
-			" replaced by the prebuilt module \"prebuilt_foo\" but unfortunately it does not provide a" +
-			" suitable boot dex jar"
+	expectedErrorMessage := "module prebuilt_foo{os:android,arch:common} does not provide a dex jar"
 
 	android.GroupFixturePreparers(
 		hiddenApiFixtureFactory,