Fix allowed STL types for system libraries.

Static libraries using the system STL have type
native:ndk:system:none, not native:ndk:system:shared, since no
actually linking takes place. These are still allowed to be linked to
platform modules.

Test: make checkbuild
Bug: None
Change-Id: Ib999bb0f422ec3938daa740fca5681e153d6525a
diff --git a/core/allowed_ndk_types.mk b/core/allowed_ndk_types.mk
index b5a85ca..3d7eac4 100644
--- a/core/allowed_ndk_types.mk
+++ b/core/allowed_ndk_types.mk
@@ -79,7 +79,11 @@
     # Else we are a non-static library that uses a static STL, and are
     # incompatible with all other shared libraries that use an STL.
 else
-    my_allowed_ndk_types := native:ndk:none:none native:ndk:system:shared
+    my_allowed_ndk_types := \
+        native:ndk:none:none \
+        native:ndk:system:none \
+        native:ndk:system:shared \
+
     ifeq ($(LOCAL_MODULE_CLASS),APPS)
         # CTS is bad and it should feel bad: http://b/13249737
         my_warn_ndk_types += native:ndk:libc++:static