Remove generated java source post clean logic

Just move the proto and renderscript sources into their own directories
-- the entire directory is wiped if the file list changes since the
command line will change. So we can just enable/disable pulling sources
from those directories based on whether there were files in the list or
not.

Bug: 30947985
Test: m -j java
Test: Remove a proto file from a java lib, ensure the generated source
      is not included.
Change-Id: If7529979de6fa62a651933a3a974f47b033851d6
diff --git a/core/java.mk b/core/java.mk
index 9199f7c..8eb30cf 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -148,7 +148,7 @@
 ifneq ($(renderscript_sources),)
 renderscript_sources_fullpath := $(addprefix $(LOCAL_PATH)/, $(renderscript_sources))
 RenderScript_file_stamp := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/RenderScript.stamp
-renderscript_intermediate.COMMON := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/renderscript
+renderscript_intermediate.COMMON := $(intermediates.COMMON)/renderscript
 
 # Defaulting to an empty string uses the latest available platform SDK.
 renderscript_target_api :=
@@ -353,6 +353,9 @@
 
 include $(BUILD_SYSTEM)/java_common.mk
 
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_HAS_RS_SOURCES := $(if $(renderscript_sources),true)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_RS_SOURCE_INTERMEDIATES_DIR := $(intermediates.COMMON)/renderscript
+
 #######################################
 # defines built_odex along with rule to install odex
 include $(BUILD_SYSTEM)/dex_preopt_odex_install.mk