libutils: use libbase_headers instead of libbase.

Bug: http://b/121391019
Test: treehugger
Change-Id: I0e5d218b9afe6f832cc6bd0ef78bc1a5581f3e2f
diff --git a/libutils/Android.bp b/libutils/Android.bp
index 600c91c..3e8417e 100644
--- a/libutils/Android.bp
+++ b/libutils/Android.bp
@@ -155,7 +155,7 @@
             ],
         },
         linux: {
-            shared_libs: ["libbase"],
+            header_libs: ["libbase_headers"],
             srcs: [
                 "Looper.cpp",
             ],