Make system use patchoat to relocate during runtime.

Change dalvik_system_DexFile.cc so that isDexOptNeededInternal will be
able to indicate that a patchoat is required. Change default of relocate
option to be on.

Bug: 15358152

Change-Id: Ibe92d8b55a24bbf718b0416a21b76e5df7a2de26
diff --git a/Android.mk b/Android.mk
index e536a71..b006bfe 100644
--- a/Android.mk
+++ b/Android.mk
@@ -316,7 +316,8 @@
 		--dex-location=/$(1) --oat-file=$$@ \
 		--instruction-set=$(DEX2OAT_TARGET_ARCH) \
 		--instruction-set-features=$(DEX2OAT_TARGET_INSTRUCTION_SET_FEATURES) \
-		--android-root=$(PRODUCT_OUT)/system --include-patch-information
+		--android-root=$(PRODUCT_OUT)/system --include-patch-information \
+		--runtime-arg -Xnorelocate
 
 endif