diff --git a/android/variable.go b/android/variable.go
index 0931db8..3f2b9e9 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -115,6 +115,10 @@
 			Static_libs  []string
 			Srcs         []string
 		}
+
+		Flatten_apex struct {
+			Enabled *bool
+		}
 	} `android:"arch_variant"`
 }
 
diff --git a/apex/apex.go b/apex/apex.go
index 832188d..70e685a 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -435,6 +435,7 @@
 
 	bundleModuleFile android.WritablePath
 	outputFiles      map[apexPackaging]android.WritablePath
+	flattenedOutput  android.OutputPath
 	installDir       android.OutputPath
 
 	prebuiltFileToDelete string
@@ -639,6 +640,13 @@
 		} else {
 			return nil, nil
 		}
+	case ".flattened":
+		if a.flattened {
+			flattenedApexPath := a.flattenedOutput
+			return android.Paths{flattenedApexPath}, nil
+		} else {
+			return nil, nil
+		}
 	default:
 		return nil, fmt.Errorf("unsupported module reference tag %q", tag)
 	}
@@ -784,6 +792,15 @@
 	return
 }
 
+// Context "decorator", overriding the InstallBypassMake method to always reply `true`.
+type flattenedApexContext struct {
+	android.ModuleContext
+}
+
+func (c *flattenedApexContext) InstallBypassMake() bool {
+	return true
+}
+
 func (a *apexBundle) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	filesInfo := []apexFile{}
 
@@ -1051,6 +1068,14 @@
 		},
 	})
 
+	// Temporarily wrap the original `ctx` into a `flattenedApexContext` to have it
+	// reply true to `InstallBypassMake()` (thus making the call
+	// `android.PathForModuleInstall` below use `android.pathForInstallInMakeDir`
+	// instead of `android.PathForOutput`) to return the correct path to the flattened
+	// APEX (as its contents is installed by Make, not Soong).
+	factx := flattenedApexContext{ctx}
+	a.flattenedOutput = android.PathForModuleInstall(&factx, "apex", factx.ModuleName())
+
 	if a.apexTypes.zip() {
 		a.buildUnflattenedApex(ctx, zipApex)
 	}
@@ -1451,6 +1476,8 @@
 					fmt.Fprintln(w, "LOCAL_REQUIRED_MODULES :=", strings.Join(moduleNames, " "))
 				}
 				fmt.Fprintln(w, "include $(BUILD_PHONY_PACKAGE)")
+				fmt.Fprintln(w, "$(LOCAL_INSTALLED_MODULE): .KATI_IMPLICIT_OUTPUTS :=", a.flattenedOutput.String())
+
 			} else {
 				// zip-apex is the less common type so have the name refer to the image-apex
 				// only and use {name}.zip if you want the zip-apex
diff --git a/cc/config/clang.go b/cc/config/clang.go
index 47b60e7..0647584 100644
--- a/cc/config/clang.go
+++ b/cc/config/clang.go
@@ -169,7 +169,6 @@
 		"-Wno-tautological-constant-compare",
 		"-Wno-tautological-type-limit-compare",
 		"-Wno-tautological-unsigned-enum-zero-compare",
-		"-Wno-tautological-unsigned-zero-compare",
 
 		// http://b/72330874 Disable -Wenum-compare until the instances detected by this new
 		// warning are fixed.
diff --git a/cc/library.go b/cc/library.go
index 6564fa1..52fd346 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -464,7 +464,7 @@
 			}
 		}
 	}
-	if enabled != nil && Bool(enabled) {
+	if Bool(enabled) || ctx.hasStubsVariants() {
 		return "PLATFORM"
 	}
 	return ""
@@ -894,7 +894,7 @@
 		}
 		exportedHeaderFlags := strings.Join(SourceAbiFlags, " ")
 		library.sAbiOutputFile = TransformDumpToLinkedDump(ctx, objs.sAbiDumpFiles, soFile, fileName, exportedHeaderFlags,
-			android.OptionalPathForModuleSrc(ctx, library.Properties.Header_abi_checker.Symbol_file),
+			android.OptionalPathForModuleSrc(ctx, library.symbolFileForAbiCheck(ctx)),
 			library.Properties.Header_abi_checker.Exclude_symbol_versions,
 			library.Properties.Header_abi_checker.Exclude_symbol_tags)
 
@@ -1095,6 +1095,16 @@
 	return library.MutatedProperties.BuildStubs
 }
 
+func (library *libraryDecorator) symbolFileForAbiCheck(ctx ModuleContext) *string {
+	if library.Properties.Header_abi_checker.Symbol_file != nil {
+		return library.Properties.Header_abi_checker.Symbol_file
+	}
+	if ctx.hasStubsVariants() && library.Properties.Stubs.Symbol_file != nil {
+		return library.Properties.Stubs.Symbol_file
+	}
+	return nil
+}
+
 func (library *libraryDecorator) stubsVersion() string {
 	return library.MutatedProperties.StubsVersion
 }
diff --git a/cc/sanitize.go b/cc/sanitize.go
index 192b8d9..72c0ecb 100644
--- a/cc/sanitize.go
+++ b/cc/sanitize.go
@@ -475,6 +475,12 @@
 		// TODO(b/133876586): Experimental PM breaks sanitizer coverage.
 		_, flags.CFlags = removeFromList("-fexperimental-new-pass-manager", flags.CFlags)
 		flags.CFlags = append(flags.CFlags, "-fno-experimental-new-pass-manager")
+
+		// Disable fortify for fuzzing builds. Generally, we'll be building with
+		// UBSan or ASan here and the fortify checks pollute the stack traces.
+		_, flags.CFlags = removeFromList("-D_FORTIFY_SOURCE=1", flags.CFlags)
+		_, flags.CFlags = removeFromList("-D_FORTIFY_SOURCE=2", flags.CFlags)
+		flags.CFlags = append(flags.CFlags, "-U_FORTIFY_SOURCE")
 	}
 
 	if Bool(sanitize.Properties.Sanitize.Cfi) {
diff --git a/cc/test.go b/cc/test.go
index aff8ba5..1a0d44f 100644
--- a/cc/test.go
+++ b/cc/test.go
@@ -68,6 +68,9 @@
 	// Add RootTargetPreparer to auto generated test config. This guarantees the test to run
 	// with root permission.
 	Require_root *bool
+
+	// Add RunCommandTargetPreparer to stop framework before the test and start it after the test.
+	Disable_framework *bool
 }
 
 func init() {
@@ -313,7 +316,13 @@
 	test.data = android.PathsForModuleSrc(ctx, test.Properties.Data)
 	var configs []tradefed.Config
 	if Bool(test.Properties.Require_root) {
-		configs = append(configs, tradefed.Preparer{"com.android.tradefed.targetprep.RootTargetPreparer"})
+		configs = append(configs, tradefed.Preparer{"com.android.tradefed.targetprep.RootTargetPreparer", nil})
+	}
+	if Bool(test.Properties.Disable_framework) {
+		var options []tradefed.Option
+		options = append(options, tradefed.Option{"run-command", "stop"})
+		options = append(options, tradefed.Option{"teardown-command", "start"})
+		configs = append(configs, tradefed.Preparer{"com.android.tradefed.targetprep.RunCommandTargetPreparer", options})
 	}
 	if Bool(test.testDecorator.Properties.Isolated) {
 		configs = append(configs, tradefed.Option{"not-shardable", "true"})
@@ -448,7 +457,7 @@
 	benchmark.data = android.PathsForModuleSrc(ctx, benchmark.Properties.Data)
 	var configs []tradefed.Config
 	if Bool(benchmark.Properties.Require_root) {
-		configs = append(configs, tradefed.Preparer{"com.android.tradefed.targetprep.RootTargetPreparer"})
+		configs = append(configs, tradefed.Preparer{"com.android.tradefed.targetprep.RootTargetPreparer", nil})
 	}
 	benchmark.testConfig = tradefed.AutoGenNativeBenchmarkTestConfig(ctx, benchmark.Properties.Test_config,
 		benchmark.Properties.Test_config_template, benchmark.Properties.Test_suites, configs)
diff --git a/java/java.go b/java/java.go
index 4ae40bf..87ee2f2 100644
--- a/java/java.go
+++ b/java/java.go
@@ -883,7 +883,7 @@
 		ctx.PropertyErrorf("sdk_version", "%s", err)
 	}
 	if javaVersion != "" {
-		ret = javaVersion
+		ret = normalizeJavaVersion(ctx, javaVersion)
 	} else if ctx.Device() && sdk <= 23 {
 		ret = "1.7"
 	} else if ctx.Device() && sdk <= 29 || !ctx.Config().TargetOpenJDK9() {
@@ -902,6 +902,25 @@
 	return ret
 }
 
+func normalizeJavaVersion(ctx android.ModuleContext, javaVersion string) string {
+	switch javaVersion {
+	case "1.6", "6":
+		return "1.6"
+	case "1.7", "7":
+		return "1.7"
+	case "1.8", "8":
+		return "1.8"
+	case "1.9", "9":
+		return "1.9"
+	case "10", "11":
+		ctx.PropertyErrorf("java_version", "Java language levels above 9 are not supported")
+		return "unsupported"
+	default:
+		ctx.PropertyErrorf("java_version", "Unrecognized Java language level")
+		return "unrecognized"
+	}
+}
+
 func (j *Module) collectBuilderFlags(ctx android.ModuleContext, deps deps) javaBuilderFlags {
 
 	var flags javaBuilderFlags
diff --git a/java/platform_compat_config.go b/java/platform_compat_config.go
index f1da203..3d46077 100644
--- a/java/platform_compat_config.go
+++ b/java/platform_compat_config.go
@@ -23,8 +23,7 @@
 }
 
 type platformCompatConfigProperties struct {
-	Src    *string `android:"path"`
-	Prefix *string
+	Src *string `android:"path"`
 }
 
 type platformCompatConfig struct {
@@ -38,13 +37,13 @@
 func (p *platformCompatConfig) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	rule := android.NewRuleBuilder()
 
-	configFileName := String(p.properties.Prefix) + "_platform_compat_config.xml"
+	configFileName := p.Name() + ".xml"
 	p.configFile = android.PathForModuleOut(ctx, configFileName).OutputPath
 	path := android.PathForModuleSrc(ctx, String(p.properties.Src))
 
 	// Use the empty config if the compat config file idoesn't exist (can happen if @ChangeId
 	// annotation is not used).
-	emptyConfig := `<?xml version="1.0" encoding="UTF-8" standalone="no"?><config/>`
+	emptyConfig := `'<?xml version="1.0" encoding="UTF-8" standalone="no"?><config/>'`
 	configPath := `compat/compat_config.xml`
 
 	rule.Command().
@@ -61,13 +60,13 @@
 		Text(configPath).
 		Text(`>`).
 		Output(p.configFile).
-		Text(`; else echo '`).
+		Text(`; else echo `).
 		Text(emptyConfig).
-		Text(`' >`).
+		Text(`>`).
 		Output(p.configFile).
 		Text(`; fi`)
 
-	p.installDirPath = android.PathForModuleInstall(ctx, "etc", "sysconfig")
+	p.installDirPath = android.PathForModuleInstall(ctx, "etc", "compatconfig")
 	rule.Build(pctx, ctx, configFileName, "Extract compat/compat_config.xml and install it")
 
 }
diff --git a/tradefed/autogen.go b/tradefed/autogen.go
index 952b022..7cd7c5a 100644
--- a/tradefed/autogen.go
+++ b/tradefed/autogen.go
@@ -24,6 +24,8 @@
 	"android/soong/android"
 )
 
+const test_xml_indent = "    "
+
 func getTestConfigTemplate(ctx android.ModuleContext, prop *string) android.OptionalPath {
 	return ctx.ExpandOptionalSource(prop, "test_config_template")
 }
@@ -72,13 +74,25 @@
 }
 
 type Preparer struct {
-	Class string
+	Class   string
+	Options []Option
 }
 
 var _ Config = Preparer{}
 
 func (p Preparer) Config() string {
-	return fmt.Sprintf(`<target_preparer class="%s" />`, p.Class)
+	var optionStrings []string
+	for _, option := range p.Options {
+		optionStrings = append(optionStrings, option.Config())
+	}
+	var options string
+	if len(p.Options) == 0 {
+		options = ""
+	} else {
+		optionDelimiter := fmt.Sprintf("\\n%s%s", test_xml_indent, test_xml_indent)
+		options = optionDelimiter + strings.Join(optionStrings, optionDelimiter)
+	}
+	return fmt.Sprintf(`<target_preparer class="%s">%s\n%s</target_preparer>`, p.Class, options, test_xml_indent)
 }
 
 func autogenTemplate(ctx android.ModuleContext, output android.WritablePath, template string, configs []Config) {
@@ -86,7 +100,7 @@
 	for _, config := range configs {
 		configStrings = append(configStrings, config.Config())
 	}
-	extraConfigs := strings.Join(configStrings, "\n        ")
+	extraConfigs := strings.Join(configStrings, fmt.Sprintf("\\n%s", test_xml_indent))
 	extraConfigs = proptools.NinjaAndShellEscape(extraConfigs)
 
 	ctx.Build(pctx, android.BuildParams{