Fix memory leak due to smart pointer misuse.

bug 11965932

Change-Id: I982b974b3554b0f4dc7a558107703ff605f580e6
diff --git a/cpp/Element.cpp b/cpp/Element.cpp
index 97a600e..b122926 100644
--- a/cpp/Element.cpp
+++ b/cpp/Element.cpp
@@ -359,7 +359,7 @@
 }
 
 Element::Builder::Builder(android::RSC::sp<RS> rs) {
-    mRS = rs;
+    mRS = rs.get();
     mSkipPadding = false;
 }