sanders: Bring up 32_64_bit support

* Do not use default core_64bit product, and ship a custom one to default run in 32bit mode

aosp_sanders.mk

@@ -17,7 +17,7 @@
 
 # Inherit from those products. Most specific first.
 $(call inherit-product, device/motorola/sanders/full_sanders.mk)
-$(call inherit-product, $(SRC_TARGET_DIR)/product/core_64_bit.mk)
+$(call inherit-product, device/motorola/sanders/core_32_64_bit.mk)
 $(call inherit-product, $(SRC_TARGET_DIR)/product/full_base_telephony.mk)
 
 # for specific

core_32_64_bit.mk

@@ -0,0 +1,33 @@
+#
+# Copyright (C) 2014 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# Inherit from this product for devices that support 64-bit apps using:
+# $(call inherit-product, $(SRC_TARGET_DIR)/product/core_64_bit.mk)
+# The inheritance for this must come before the inheritance chain that leads
+# to core_minimal.mk
+
+# For now this will allow 64-bit apps, but still compile all apps with JNI
+# for 32-bit only.
+
+# Copy the 32-bit primary, 64-bit secondary zygote startup script
+PRODUCT_COPY_FILES += system/core/rootdir/init.zygote32_64.rc:root/init.zygote32_64.rc
+
+# Set the zygote property to select the 32-bit primary, 64-bit secondary script
+# This line must be parsed before the one in core_minimal.mk
+PRODUCT_DEFAULT_PROPERTY_OVERRIDES += ro.zygote=zygote32_64
+
+TARGET_SUPPORTS_32_BIT_APPS := true
+TARGET_SUPPORTS_64_BIT_APPS := true