Compile boot image on host.

Compile even though it might not be used yet.
This is intermediate step for switching golem to core.art.

Test: Run some golem benchmarks locally.
Bug: 147817558
Bug: 147819342
Change-Id: I29ef8adf6729723858e2409e5ac6d2ab3b8628d3
diff --git a/build/Android.common_path.mk b/build/Android.common_path.mk
index 6aa3b42..1d67037 100644
--- a/build/Android.common_path.mk
+++ b/build/Android.common_path.mk
@@ -94,6 +94,8 @@
 $(HOST_OUT)/apex/com.android.conscrypt/javalib/conscrypt.jar : $(HOST_OUT_JAVA_LIBRARIES)/conscrypt-hostdex.jar
 	$(copy-file-to-target)
 
+HOST_CORE_IMG_OUTS += $(HOST_BOOT_IMAGE_JARS) $(HOST_BOOT_IMAGE) $(2ND_HOST_BOOT_IMAGE)
+
 HOST_TEST_CORE_JARS   := $(addsuffix -hostdex,$(CORE_IMG_JARS) conscrypt)
 ART_HOST_DEX_DEPENDENCIES := $(foreach jar,$(HOST_TEST_CORE_JARS),$(HOST_OUT_JAVA_LIBRARIES)/$(jar).jar)
 ART_TARGET_DEX_DEPENDENCIES := com.android.art.testing com.android.conscrypt