Set '--force-determinism' option for boot image compilation.

Test: aosp_walleye-userdebug boots.
Change-Id: I0edf7fbfe18ea2f3d1cfda5138a48bdc1420aa6a

Bug: 150934453
diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index d7adb40..6ec919c 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -379,6 +379,7 @@
 		FlagWithArg("--instruction-set-features=", global.InstructionSetFeatures[arch]).
 		FlagWithArg("--android-root=", global.EmptyDirectory).
 		FlagWithArg("--no-inline-from=", "core-oj.jar").
+		Flag("--force-determinism").
 		Flag("--abort-on-hard-verifier-error")
 
 	if global.BootFlags != "" {