Merge changes from topics "target-build-unbundled", "unbundled-preopt"

* changes:
  Don't disable dexpreopting implicitly in unbundled builds.
  Add TARGET_BUILD_UNBUNDLED as a variable to control builds.
diff --git a/java/dexpreopt.go b/java/dexpreopt.go
index 2911fd9..c33415e 100644
--- a/java/dexpreopt.go
+++ b/java/dexpreopt.go
@@ -77,10 +77,6 @@
 		return true
 	}
 
-	if ctx.Config().UnbundledBuild() {
-		return true
-	}
-
 	if d.isTest {
 		return true
 	}
diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index 9d93838..4096c66 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -179,15 +179,7 @@
 }
 
 func skipDexpreoptBootJars(ctx android.PathContext) bool {
-	if dexpreopt.GetGlobalConfig(ctx).DisablePreopt {
-		return true
-	}
-
-	if ctx.Config().UnbundledBuild() {
-		return true
-	}
-
-	return false
+	return dexpreopt.GetGlobalConfig(ctx).DisablePreopt
 }
 
 type dexpreoptBootJars struct {
diff --git a/ui/build/config.go b/ui/build/config.go
index 49f506e..c4bbad7 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -592,6 +592,7 @@
 	c.environ.Set("TARGET_BUILD_VARIANT", variant)
 	c.environ.Set("TARGET_BUILD_TYPE", "release")
 	c.environ.Unset("TARGET_BUILD_APPS")
+	c.environ.Unset("TARGET_BUILD_UNBUNDLED")
 }
 
 // Tapas configures the environment to build one or more unbundled apps,
diff --git a/ui/build/dumpvars.go b/ui/build/dumpvars.go
index 7dc4915..e229856 100644
--- a/ui/build/dumpvars.go
+++ b/ui/build/dumpvars.go
@@ -143,6 +143,7 @@
 	"TARGET_BUILD_VARIANT",
 	"TARGET_BUILD_TYPE",
 	"TARGET_BUILD_APPS",
+	"TARGET_BUILD_UNBUNDLED",
 	"TARGET_ARCH",
 	"TARGET_ARCH_VARIANT",
 	"TARGET_CPU_VARIANT",
@@ -187,6 +188,7 @@
 		"TARGET_PRODUCT",
 		"TARGET_BUILD_VARIANT",
 		"TARGET_BUILD_APPS",
+		"TARGET_BUILD_UNBUNDLED",
 
 		// compiler wrappers set up by make
 		"CC_WRAPPER",