Add FORCE_BUILD_RS_COMPAT option.

This enables the .so libraries to be built for apps using the
RenderScript support library. Traditionally, we trim these .so
files from full platform builds.

Change-Id: I6f8e9b8d2b671338d3d5a5ac0bfcc60fd448688b
diff --git a/core/java.mk b/core/java.mk
index 1e2e6a6..66ba9ca 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -195,7 +195,7 @@
 
 # We don't need the .so files in bundled branches
 # Prevent these from showing up on the device
-ifneq (,$(TARGET_BUILD_APPS))
+ifneq (,$(TARGET_BUILD_APPS)$(FORCE_BUILD_RS_COMPAT))
 
 rs_compatibility_jni_libs := $(addprefix \
     $(renderscript_intermediate)/librs., \