Move imageMutator before archMutator

Run the imageMutator between osMutator and archMutator so that
different arch variants can be set for the different partitions.

Bug: 142286466
Test: m checkbuild
Change-Id: I65d05714b75aa462bf9816da60fdc2deda4de593
Merged-In: I65d05714b75aa462bf9816da60fdc2deda4de593
(cherry picked from commit 9c8f687584986f6e36ebfdbda22c3cc6c21cf02d)
diff --git a/android/mutator.go b/android/mutator.go
index e9ccd7f..c2bae44 100644
--- a/android/mutator.go
+++ b/android/mutator.go
@@ -87,9 +87,9 @@
 
 func registerArchMutator(ctx RegisterMutatorsContext) {
 	ctx.BottomUp("os", osMutator).Parallel()
+	ctx.BottomUp("image", imageMutator).Parallel()
 	ctx.BottomUp("arch", archMutator).Parallel()
 	ctx.TopDown("arch_hooks", archHookMutator).Parallel()
-	ctx.BottomUp("image", imageMutator).Parallel()
 }
 
 var preDeps = []RegisterMutatorFunc{