Rename ART dump-oat rules.

Follow-up to CL/1235086 which renamed the rules.

Preserve the name for target since ART tests depends on it.

Test: m dump-oat-boot-x86
Change-Id: I67c7ea9e99fea24f089d38856811bfa320258b54
diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index 7ccf828..8e621c7 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -547,7 +547,11 @@
 	var allPhonies android.Paths
 	for _, image := range image.variants {
 		arch := image.target.Arch.ArchType
-		suffix := image.target.String()
+		suffix := arch.String()
+		// Host and target might both use x86 arch. We need to ensure the names are unique.
+		if image.target.Os.Class == android.Host {
+			suffix = "host-" + suffix
+		}
 		// Create a rule to call oatdump.
 		output := android.PathForOutput(ctx, "boot."+suffix+".oatdump.txt")
 		rule := android.NewRuleBuilder()
@@ -570,7 +574,10 @@
 			Text("echo").FlagWithArg("Output in ", output.String())
 		rule.Build(pctx, ctx, "phony-dump-oat-boot-"+suffix, "dump oat boot "+arch.String())
 
-		allPhonies = append(allPhonies, phony)
+		// TODO: We need to make imageLocations per-variant to make oatdump work on host.
+		if image.target.Os == android.Android {
+			allPhonies = append(allPhonies, phony)
+		}
 	}
 
 	phony := android.PathForPhony(ctx, "dump-oat-boot")