Introduce anonymous namespace

The anonymous namespace is introduced to
handle cases when linker can not find the
caller. This usually happens when caller
code was not loaded by dynamic linker;
for example mono-generated code.

Bug: http://b/25844435
Bug: http://b/22548808
Change-Id: I9e5b1d23c1c75bc78548d68e79216a6a943a33cf
diff --git a/libdl/libdl.arm.map b/libdl/libdl.arm.map
index 3417f99..5ad9f9d 100644
--- a/libdl/libdl.arm.map
+++ b/libdl/libdl.arm.map
@@ -16,7 +16,7 @@
 
 LIBC_N {
   global:
-    android_init_public_namespace;
+    android_init_namespaces;
     android_create_namespace;
 } LIBC;