Remove Core Library JARs from /system/framework.

These JARs are part of the ART APEX, and are now located in
`/apex/com.android.art/javalib`. Remove the supernumerary copies in
`/system/framework` and save ~11 MiB on the system partition.

Test: Device boot test
Bug: 142944799
Change-Id: Ia6f58d858ecdb80c9701696b8f20d5fa2de0c2c7

CleanSpec.mk

@@ -690,6 +690,10 @@ $(call add-clean-step, rm -rf $(PRODUCT_OUT)/*/*app/*/oat)
 # Migrate preopt files from system_other for some devices
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system_other)
 
+# Remove Android Core Library artifacts from the system partition, now
+# that they live in the ART APEX (b/142944799).
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/framework/*.jar)
+
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************

core/main.mk

@@ -1255,6 +1255,8 @@ else
   endef
 endif
 
+# TODO(b/142944799): Implement Java library absence check for Core Libraries.
+
 ifdef FULL_BUILD
   ifneq (true,$(ALLOW_MISSING_DEPENDENCIES))
     # Check to ensure that all modules in PRODUCT_PACKAGES exist (opt in per product)

target/product/runtime_libart.mk

@@ -20,11 +20,6 @@ ifeq ($(TARGET_CORE_JARS),)
 $(error TARGET_CORE_JARS is empty; cannot update PRODUCT_PACKAGES variable)
 endif
 
-# Minimal boot classpath. This should be a subset of PRODUCT_BOOT_JARS, and equivalent to
-# TARGET_CORE_JARS.
-PRODUCT_PACKAGES += \
-    $(TARGET_CORE_JARS)
-
 # Additional mixins to the boot classpath.
 PRODUCT_PACKAGES += \
     android.test.base \
@@ -37,6 +32,9 @@ PRODUCT_PACKAGES += \
 PRODUCT_PACKAGES += com.android.runtime
 
 # ART APEX module.
+# Note that this package includes the minimal boot classpath JARs (listed in
+# TARGET_CORE_JARS), which should no longer be added directly to
+# PRODUCT_PACKAGES.
 PRODUCT_PACKAGES += com.android.art
 PRODUCT_HOST_PACKAGES += com.android.art