Add fake libart

Bug: 27775991

Change-Id: I54cbdf2340dcfdd9b3973d9d10c8bd94492736fb
(cherry picked from commit 6da74d8f1f0a06366fe93b885dc26f53401ec6b4)
diff --git a/target/product/runtime_libart.mk b/target/product/runtime_libart.mk
index 3782869..85c5b1e 100644
--- a/target/product/runtime_libart.mk
+++ b/target/product/runtime_libart.mk
@@ -35,6 +35,7 @@
     ext \
     hprof-conv \
     libart \
+    libart_fake \
     libcrypto \
     libexpat \
     libicui18n \