Split [CC|CXX]_WRAPPER from [TARGET|HOST]_[CC|CXX]

- Don't overwrite [TARGET|HOST]_[CC|CXX] with the [CC|CXX]_WRAPPER prefix,
  so that we can disable the wrapper per module.
- Disable ccache on a module when FDO is enabled.

Bug: 22612634
Change-Id: Ibc04a4742d589955066c7eceb43a0da9a2b893bc
diff --git a/core/java.mk b/core/java.mk
index b371289..0ff59fc 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -253,7 +253,7 @@
 $(rs_compatibility_jni_libs): $(RenderScript_file_stamp) $(RS_PREBUILT_CLCORE) \
     $(rs_support_lib) $(rs_support_io_lib) $(rs_jni_lib) $(rs_compiler_rt)
 $(rs_compatibility_jni_libs): $(BCC_COMPAT)
-$(rs_compatibility_jni_libs): PRIVATE_CXX := $(TARGET_CXX)
+$(rs_compatibility_jni_libs): PRIVATE_CXX := $(CXX_WRAPPER) $(TARGET_CXX)
 $(rs_compatibility_jni_libs): $(renderscript_intermediate)/librs.%.so: \
     $(renderscript_intermediate.bc_folder)%.bc
 	$(transform-bc-to-so)