Make art script work for the first time

Change-Id: Iab8d5e1e3abf372d7a7a567bce55becdb5a139d7
diff --git a/tools/art b/tools/art
index 0d993ca..6af2151 100755
--- a/tools/art
+++ b/tools/art
@@ -33,15 +33,11 @@
   fi
 done
 
+unset ANDROID_PRODUCT_OUT # avoid defaulting dex2oat --host-prefix to target output
 mkdir -p /tmp/android-data/art-cache
-ANDROID_DATA=/tmp/android-data \
-ANDROID_ROOT=$ANDROID_HOST_OUT \
-LD_LIBRARY_PATH=$ANDROID_HOST_OUT/lib \
-$invoke_with $ANDROID_HOST_OUT/bin/$oatexec \
--Xbootclasspath\
-:$ANDROID_HOST_OUT/framework/core-hostdex.jar\
-:$ANDROID_HOST_OUT/framework/core-junit-hostdex.jar\
-:$ANDROID_HOST_OUT/framework/core-tests-hostdex.jar\
-:$ANDROID_HOST_OUT/framework/bouncycastle-hostdex.jar\
-:$ANDROID_HOST_OUT/framework/apache-xml-hostdex.jar \
-$*
+ANDROID_DATA=/tmp/android-data\
+ ANDROID_ROOT=$ANDROID_HOST_OUT\
+ LD_LIBRARY_PATH=$ANDROID_HOST_OUT/lib\
+ $invoke_with $ANDROID_HOST_OUT/bin/$oatexec\
+ -Ximage:$ANDROID_HOST_OUT/framework/core.art \
+ $*