Add dependencies on the makefiles.

I've been enjoying this in bionic for a while now, and was annoyed
not to have make do the right thing in libcore.

Change-Id: Idcd2db48349202259887499a1f47d85c5d205d54
diff --git a/NativeCode.mk b/NativeCode.mk
index fae0fce..1aab901 100644
--- a/NativeCode.mk
+++ b/NativeCode.mk
@@ -53,6 +53,7 @@
 # set up.
 include $(CLEAR_VARS)
 LOCAL_MODULE := $(core_magic_local_target)
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/NativeCode.mk
 core_src_files :=
 
 # Include the sub.mk files.
@@ -88,6 +89,7 @@
 LOCAL_STATIC_LIBRARIES := $(core_static_libraries)
 LOCAL_MODULE_TAGS := optional
 LOCAL_MODULE := libjavacore
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/NativeCode.mk
 
 LOCAL_C_INCLUDES += external/stlport/stlport bionic/ bionic/libstdc++/include
 LOCAL_SHARED_LIBRARIES += libstlport
@@ -108,6 +110,7 @@
     LOCAL_LDLIBS += -ldl -lpthread
     LOCAL_MODULE_TAGS := optional
     LOCAL_MODULE := libjavacore
+    LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/NativeCode.mk
     LOCAL_SHARED_LIBRARIES := $(core_shared_libraries) libexpat libicuuc libicui18n libssl libcrypto libz-host
     LOCAL_STATIC_LIBRARIES := $(core_static_libraries)
     include $(BUILD_HOST_SHARED_LIBRARY)