Install dexpreopt artifacts of apex system server jars in same partition

e.g. If a system server jar providing apex is installed in /system_ext,
the dexpreopt files of that jar will also be installed in /system_ext.
Currently, all of these artifacts are installed in /system

This behavior will be flag guarded by
RELEASE_INSTALL_APEX_SYSTEMSERVER_DEXPREOPT_SAME_PARTITION. This is
necessary because the ART runtime needs to be updated to look in the new
/system_ext location. Since some release configs build with ART
prebuilts, the runtime in those prebuilt apexes will not have the
additional search path introduced in https://r.android.com/3287191

Test: Verified that "Could not check odex file" does not appear for
service-compos (a system_ext apex systemserver jar)

Bug: 369678122
Change-Id: I752bdc7f5f69226b503800ce25726a211302cb07
diff --git a/dexpreopt/dexpreopt.go b/dexpreopt/dexpreopt.go
index 5616483..7a39fa1 100644
--- a/dexpreopt/dexpreopt.go
+++ b/dexpreopt/dexpreopt.go
@@ -219,9 +219,9 @@
 }
 
 // Returns the location to the odex file for the dex file at `path`.
-func ToOdexPath(path string, arch android.ArchType) string {
+func ToOdexPath(path string, arch android.ArchType, partition string) string {
 	if strings.HasPrefix(path, "/apex/") {
-		return filepath.Join("/system/framework/oat", arch.String(),
+		return filepath.Join(partition, "framework/oat", arch.String(),
 			strings.ReplaceAll(path[1:], "/", "@")+"@classes.odex")
 	}
 
@@ -245,7 +245,7 @@
 
 	odexPath := module.BuildPath.InSameDir(ctx, "oat", arch.String(), pathtools.ReplaceExtension(base, "odex"))
 	odexSymbolsPath := odexPath.ReplaceExtension(ctx, "symbols.odex")
-	odexInstallPath := ToOdexPath(module.DexLocation, arch)
+	odexInstallPath := ToOdexPath(module.DexLocation, arch, module.ApexPartition)
 	if odexOnSystemOther(module, global) {
 		odexInstallPath = filepath.Join(SystemOtherPartition, odexInstallPath)
 	}