Remove typo'd variables

LOCAL_DEX_PREOPT_IMAGE_LOCATION := $(TARGET_CORE_IMG_OUT) doesn't
do anything because TARGET_CORE_IMG_OUT is never set.

LOCAL_DEX_PREOPT_IMAGE := $(HOST_CORE_IMG_LOCATION) doesn't do
anything because nothing reads LOCAL_DEX_PREOPT_IMAGE.

Neither seems useful with LOCAL_DEX_PREOPT := false.

Test: m checkbuild
Change-Id: I26c0a848e15784c4dad6f8c3bb6786b98ac85c20
diff --git a/build/Android.common_test.mk b/build/Android.common_test.mk
index 12eae89..55b8ae2 100644
--- a/build/Android.common_test.mk
+++ b/build/Android.common_test.mk
@@ -127,7 +127,6 @@
     LOCAL_MODULE_TAGS := tests
     LOCAL_JAVA_LIBRARIES := $(TARGET_TEST_CORE_JARS)
     LOCAL_MODULE_PATH := $(3)
-    LOCAL_DEX_PREOPT_IMAGE_LOCATION := $(TARGET_CORE_IMG_OUT)
     ifneq ($(wildcard $(LOCAL_PATH)/$(2)/main.list),)
       LOCAL_MIN_SDK_VERSION := 19
       LOCAL_DX_FLAGS := --multi-dex --main-dex-list=$(LOCAL_PATH)/$(2)/main.list --minimal-main-dex
@@ -143,7 +142,6 @@
     LOCAL_DEX_PREOPT := false
     LOCAL_ADDITIONAL_DEPENDENCIES := art/build/Android.common_test.mk $(4)
     LOCAL_JAVA_LIBRARIES := $(HOST_TEST_CORE_JARS)
-    LOCAL_DEX_PREOPT_IMAGE := $(HOST_CORE_IMG_LOCATION)
     ifneq ($(wildcard $(LOCAL_PATH)/$(2)/main.list),)
       LOCAL_MIN_SDK_VERSION := 19
       LOCAL_DX_FLAGS := --multi-dex --main-dex-list=$(LOCAL_PATH)/$(2)/main.list --minimal-main-dex