linker: implement shared namespaces

Shared namespaces clone the list of loaded native
libraries from the caller namespace. This allows
classloaders for bundled apps to share already loaded
libraries with default namespace.

Bug: http://b/22548808
Bug: http://b/26165097
Change-Id: I8949d45937fdb38e1f586ff0679003adac0d9dad
(cherry picked from commit e78deef364d952dd1141a2f3067a12060aaf11e6)
diff --git a/linker/linker.h b/linker/linker.h
index 5ec259e..5a06853 100644
--- a/linker/linker.h
+++ b/linker/linker.h
@@ -444,8 +444,8 @@
 uint32_t get_application_target_sdk_version();
 
 bool init_namespaces(const char* public_ns_sonames, const char* anon_ns_library_path);
-android_namespace_t* create_namespace(const char* name, const char* ld_library_path,
-                                      const char* default_library_path, bool is_isolated,
-                                      const char* permitted_when_isolated_path);
+android_namespace_t* create_namespace(const void* caller_addr, const char* name,
+                                      const char* ld_library_path, const char* default_library_path,
+                                      uint64_t type, const char* permitted_when_isolated_path);
 
 #endif