core: Move core.oat bootjar definitions into core/config

TARGET_CORE_JARS and HOST_CORE_JARS define the minimal
bootclasspath jars necessary to run with dalvikvm/art.

Also refactor PRODUCT_BOOT_JARS to reuse TARGET_CORE_JARS.

(These changes are required to figure out what --bootclasspath_entry
to pass to desugar).

Bug: 36902714
Test: make -j32 && make -j32 build-art-host build-art-target
Change-Id: I620e28be41047a1d501d7f144fe415ee4a0af36f
diff --git a/core/config.mk b/core/config.mk
index 5ff582a..32fcf44 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -799,6 +799,13 @@
 SUPPORT_LIBRARY_ROOT := frameworks/support
 endif
 
+#################################################################
+# Set up minimal BOOTCLASSPATH list of jars to build/execute
+# java code with dalvikvm/art.
+#################################################################
+TARGET_CORE_JARS := core-oj core-libart conscrypt okhttp bouncycastle apache-xml
+HOST_CORE_JARS := $(addsuffix -hostdex,$(TARGET_CORE_JARS))
+
 # Historical SDK version N is stored in $(HISTORICAL_SDK_VERSIONS_ROOT)/N.
 # The 'current' version is whatever this source tree is.
 #
diff --git a/target/product/core_tiny.mk b/target/product/core_tiny.mk
index 2fb450d..cea6bce 100644
--- a/target/product/core_tiny.mk
+++ b/target/product/core_tiny.mk
@@ -85,18 +85,13 @@
 
 # The order matters
 PRODUCT_BOOT_JARS := \
-    core-oj \
-    core-libart \
-    conscrypt \
-    okhttp \
+    $(TARGET_CORE_JARS) \
     legacy-test \
-    bouncycastle \
     ext \
     framework \
     telephony-common \
     voip-common \
     ims-common \
-    apache-xml \
     nullwebview \
     org.apache.http.legacy.boot