Create the installation rules of host ART boot image in soong

The build rules for these are generated by soong, but currently make is
used to create the installation rules. This CL moves the installation
rules to soong.

Details
- Introduced a `art_boot_images` module type. This is a regular
  module, and not a singleton module (singleton modules for host are not
supported by soong today)
- `art_boot_images` will create a dependency on `dex_bootjars`
- In GenerateAndroidBuildActions of `dex_bootjars`, it will set a
  provider with the install info of host ART boot image files
- In GenerateAndroidBuildActions of `art_boot_images`, the
  installation rules will be created using `ctx.InstallFile`

Bug: 355706080
Test: m installclean && m test-art-host-gtest (gtests)
Test: m installclean && m test-art-host-run-test-dependencies &&
art/test.py --host (art run-tests)

Change-Id: I9c3e6c6c01890facb758cdabef2a83f6990a06c9
diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index a2e4734..ad0e0a7 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -463,6 +463,7 @@
 
 func RegisterDexpreoptBootJarsComponents(ctx android.RegistrationContext) {
 	ctx.RegisterParallelSingletonModuleType("dex_bootjars", dexpreoptBootJarsFactory)
+	ctx.RegisterModuleType("art_boot_images", artBootImagesFactory)
 	ctx.FinalDepsMutators(func(ctx android.RegisterMutatorsContext) {
 		ctx.BottomUp("dex_bootjars_deps", DexpreoptBootJarsMutator).Parallel()
 	})
@@ -601,6 +602,7 @@
 	d.defaultBootImage = defaultBootImageConfig(ctx)
 	d.otherImages = make([]*bootImageConfig, 0, len(imageConfigs)-1)
 	var profileInstalls android.RuleBuilderInstalls
+	var artBootImageHostInstalls android.RuleBuilderInstalls
 	for _, name := range getImageNames() {
 		config := imageConfigs[name]
 		if config != d.defaultBootImage {
@@ -616,6 +618,18 @@
 			d.bootFrameworkProfile = bootProfile
 			profileInstalls = append(profileInstalls, installs...)
 		}
+		// Gather the install files of the host variant of the ART boot image.
+		// These installed files will be used in ART tests.
+		if config.name == "art" {
+			for _, variant := range config.variants {
+				if variant.target.Os != ctx.Config().BuildOS {
+					// not a host variant
+					continue
+				}
+				artBootImageHostInstalls = append(artBootImageHostInstalls, variant.installs...)
+				artBootImageHostInstalls = append(artBootImageHostInstalls, variant.vdexInstalls...)
+			}
+		}
 	}
 	if len(profileInstalls) > 0 {
 		android.SetProvider(ctx, profileInstallInfoProvider, profileInstallInfo{
@@ -626,6 +640,15 @@
 			installFile(ctx, install)
 		}
 	}
+	// Set a provider containing the install files of the host variant of the ART boot image.
+	// The actual install rules will be created by `art_boot_images`
+	android.SetProvider(
+		ctx,
+		artBootImageHostInfoProvider,
+		artBootImageHostInfo{
+			installs: artBootImageHostInstalls,
+		},
+	)
 }
 
 // GenerateSingletonBuildActions generates build rules for the dexpreopt config for Make.
@@ -968,6 +991,14 @@
 	}
 }
 
+var artBootImageHostInfoProvider = blueprint.NewProvider[artBootImageHostInfo]()
+
+// artBootImageHostInfo contains the install locations of the host variant of ART boot image
+// this contains both the primary and secondary arch locations
+type artBootImageHostInfo struct {
+	installs android.RuleBuilderInstalls
+}
+
 // Generate boot image build rules for a specific target.
 func buildBootImageVariant(ctx android.ModuleContext, image *bootImageVariant, profile android.Path) bootImageVariantOutputs {
 
@@ -1396,3 +1427,70 @@
 		OutputFile: android.OptionalPathForPath(d.bootFrameworkProfile),
 	}}
 }
+
+// artBootImages is a thin wrapper around `dex_bootjars`.
+// it creates the installation rules for the host variant of the ART boot image.
+type artBootImages struct {
+	android.ModuleBase
+
+	// A non-empty file that will be written as `LOCAL_SOONG_INSTALLED_MODULE` in out/soong/Android-*.mk
+	outputFile android.OptionalPath
+}
+
+func artBootImagesFactory() android.Module {
+	m := &artBootImages{}
+	android.InitAndroidMultiTargetsArchModule(m, android.HostSupported, android.MultilibCommon)
+	return m
+}
+
+func (dbj *artBootImages) DepsMutator(ctx android.BottomUpMutatorContext) {
+	// Create a dependency on `dex_bootjars` to access the intermediate locations of host art boot image.
+	ctx.AddDependency(ctx.Module(), dexpreoptBootJarDepTag, "dex_bootjars")
+}
+
+func (d *artBootImages) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	ctx.VisitDirectDepsWithTag(dexpreoptBootJarDepTag, func(m android.Module) {
+		hostInstallsInfo, ok := android.OtherModuleProvider(ctx, m, artBootImageHostInfoProvider)
+		if !ok {
+			ctx.ModuleErrorf("Could not find information about the host variant of ART boot image")
+		}
+		installs := d.installFile(ctx, hostInstallsInfo.installs)
+		if len(installs) > 0 {
+			d.outputFile = android.OptionalPathForPath(installs[0])
+			// Create a phony target that can ART run-tests can depend on.
+			ctx.Phony(d.Name(), installs...)
+		} else {
+			// this might be true e.g. when building with `WITH_DEXPREOPT=false`
+			// create an empty file so that the `art_boot_images` is known to the packaging system.
+			d.outputFile = android.OptionalPathForPath(android.PathForModuleOut(ctx, "undefined_art_boot_images"))
+		}
+	})
+}
+
+// Creates an installation rule for host variant of ART boot image files.
+// Returns the list of install locations (out/host/linux-x86/...)
+func (d *artBootImages) installFile(ctx android.ModuleContext, ruleBuilderInstalls android.RuleBuilderInstalls) android.Paths {
+	var ret android.Paths
+	for _, ruleBuilderInstall := range ruleBuilderInstalls {
+		installDir := android.PathForModuleInstall(
+			ctx,
+			strings.TrimPrefix(filepath.Dir(ruleBuilderInstall.To), "/"),
+		)
+		filename := filepath.Base(ruleBuilderInstall.To)
+		ctx.InstallFile(
+			installDir,
+			filename,
+			ruleBuilderInstall.From,
+		)
+		ret = append(ret, installDir.Join(ctx, filename))
+	}
+	return ret
+}
+
+// Set `OutputFile` expclitly so that this module does not get elided when generating out/soong/Android-*.mk
+func (d *artBootImages) AndroidMkEntries() []android.AndroidMkEntries {
+	return []android.AndroidMkEntries{{
+		Class:      "ETC",
+		OutputFile: d.outputFile,
+	}}
+}