Merge changes I7642c57b,I2120b40e

* changes:
  apex uses the first arch variant of prebuilt_etc modules
  sh_binary prefer 32bit when TARGET_PREFER_32_BIT

android/sh_binary.go

@@ -196,6 +196,9 @@ func InitShBinaryModule(s *ShBinary) {
 // executable binary to <partition>/bin.
 func ShBinaryFactory() Module {
 	module := &ShBinary{}
+	module.Prefer32(func(ctx BaseModuleContext, base *ModuleBase, class OsClass) bool {
+		return class == Device && ctx.Config().DevicePrefer32BitExecutables()
+	})
 	InitShBinaryModule(module)
 	InitAndroidArchModule(module, HostAndDeviceSupported, MultilibFirst)
 	return module

apex/apex.go

@@ -598,10 +598,6 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 				a.properties.Multilib.First.Tests,
 				target,
 				a.getImageVariation(config))
-
-			// When multilib.* is omitted for prebuilts, it implies multilib.first.
-			ctx.AddFarVariationDependencies(target.Variations(),
-				prebuiltTag, a.properties.Prebuilts...)
 		}
 
 		switch target.Arch.ArchType.Multilib {
@@ -652,6 +648,22 @@ func (a *apexBundle) DepsMutator(ctx android.BottomUpMutatorContext) {
 
 	}
 
+	// For prebuilt_etc, use the first variant (64 on 64/32bit device,
+	// 32 on 32bit device) regardless of the TARGET_PREFER_* setting.
+	// b/144532908
+	archForPrebuiltEtc := config.Arches()[0]
+	for _, arch := range config.Arches() {
+		// Prefer 64-bit arch if there is any
+		if arch.ArchType.Multilib == "lib64" {
+			archForPrebuiltEtc = arch
+			break
+		}
+	}
+	ctx.AddFarVariationDependencies([]blueprint.Variation{
+		{Mutator: "os", Variation: ctx.Os().String()},
+		{Mutator: "arch", Variation: archForPrebuiltEtc.String()},
+	}, prebuiltTag, a.properties.Prebuilts...)
+
 	ctx.AddFarVariationDependencies(ctx.Config().AndroidCommonTarget.Variations(),
 		javaLibTag, a.properties.Java_libs...)