Remove MutatorHandle.Parallel()

All mutators are parallel by default, remove the explicit Parallel()
calls.

Bug: 372540665
Test: all soong tests pass
Flag: EXEMPT refactor
Change-Id: I41e3a71bd13c75b7fceae91b1c4cfe678ab62df2
diff --git a/java/java.go b/java/java.go
index 018850f..4a1f2d9 100644
--- a/java/java.go
+++ b/java/java.go
@@ -70,9 +70,9 @@
 	// established, to not get the dependencies split into the wrong variants and
 	// to support the checks in dexpreoptDisabled().
 	ctx.FinalDepsMutators(func(ctx android.RegisterMutatorsContext) {
-		ctx.BottomUp("dexpreopt_tool_deps", dexpreoptToolDepsMutator).Parallel()
+		ctx.BottomUp("dexpreopt_tool_deps", dexpreoptToolDepsMutator)
 		// needs access to ApexInfoProvider which is available after variant creation
-		ctx.BottomUp("jacoco_deps", jacocoDepsMutator).Parallel()
+		ctx.BottomUp("jacoco_deps", jacocoDepsMutator)
 	})
 
 	ctx.RegisterParallelSingletonType("kythe_java_extract", kytheExtractJavaFactory)