Support custom RenderScript compiler

Change-Id: I85e38e84565e04f99dd26217f280274883dc322d
diff --git a/core/java.mk b/core/java.mk
index 0397deb..464f772 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -148,12 +148,17 @@
      $(LOCAL_RENDERSCRIPT_INCLUDES)
 endif
 
+ifeq ($(LOCAL_RENDERSCRIPT_CC),)
+LOCAL_RENDERSCRIPT_CC := $(LLVM_RS_CC)
+endif
+
 $(RenderScript_file_stamp): PRIVATE_RS_INCLUDES := $(LOCAL_RENDERSCRIPT_INCLUDES)
+$(RenderScript_file_stamp): PRIVATE_RS_CC := $(LOCAL_RENDERSCRIPT_CC)
 $(RenderScript_file_stamp): PRIVATE_RS_SOURCE_FILES := $(renderscript_sources_fullpath)
 # By putting the generated java files into $(LOCAL_INTERMEDIATE_SOURCE_DIR), they will be
 # automatically found by the java compiling function transform-java-to-classes.jar.
 $(RenderScript_file_stamp): PRIVATE_RS_OUTPUT_DIR := $(renderscript_intermediate)
-$(RenderScript_file_stamp): $(renderscript_sources_fullpath) $(LLVM_RS_CC)
+$(RenderScript_file_stamp): $(renderscript_sources_fullpath) $(LOCAL_RENDERSCRIPT_CC)
 	$(transform-renderscripts-to-java-and-bc)
 
 # include the dependency files (.d) generated by llvm-rs-cc.