Read all product makefiles even when TARGET_BUILD_APPS is set

This allows us to have vendor-specific product makefiles for building
unbundled artifacts. The makefile could be used to specify path to the
keystore used to sign the artifacts for the vendor.

Bug: 121224311
Test: m
Change-Id: I260bfddc5fc438fc0986b39d9010087bf758c7ca
diff --git a/core/product_config.mk b/core/product_config.mk
index ac7fe91..f0f7da1 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -175,15 +175,9 @@
 include $(BUILD_SYSTEM)/product.mk
 include $(BUILD_SYSTEM)/device.mk
 
-ifneq ($(strip $(TARGET_BUILD_APPS)),)
-# An unbundled app build needs only the core product makefiles.
-all_product_configs := $(call get-product-makefiles,\
-    $(SRC_TARGET_DIR)/product/AndroidProducts.mk)
-else
 # Read in all of the product definitions specified by the AndroidProducts.mk
 # files in the tree.
 all_product_configs := $(get-all-product-makefiles)
-endif
 
 all_named_products :=