Add support for oat files in /data/art-cache

Also implement Zygote_nativeForkAndSpecialize

Change-Id: I7dfb257b2897279a4cdac4b1ca194c1ac84eb047
diff --git a/src/utils.h b/src/utils.h
index 228925d..7778918 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -212,6 +212,9 @@
 // implementation-defined limit.
 void SetThreadName(const char* name);
 
+// Returns the art-cache location or dies trying
+std::string GetArtCacheOrDie();
+
 }  // namespace art
 
 #endif  // ART_SRC_UTILS_H_