Add ECPrivateKey for Elliptic Curve keypair generation.

crypto/scoped_nss_types.h

Index: crypto/scoped_nss_types.h
diff --git a/crypto/scoped_nss_types.h b/crypto/scoped_nss_types.h
index d8d78b0592d3838810520807b7850c443f7c1502..9bb9968864052ecdf74ce47bf1aa4e58e67c43ce 100644
--- a/crypto/scoped_nss_types.h
+++ b/crypto/scoped_nss_types.h
@@ -9,6 +9,7 @@
 #include <keyhi.h>
 #include <nss.h>
 #include <pk11pub.h>
+#include <plarena.h>
 
 #include "base/memory/scoped_ptr.h"
 
@@ -53,6 +54,10 @@ typedef scoped_ptr_malloc<
     SECItem, NSSDestroyer1<SECItem,
                            SECITEM_FreeItem,
                            PR_TRUE> > ScopedSECItem;
+typedef scoped_ptr_malloc<
+    PLArenaPool, NSSDestroyer1<PLArenaPool,
+                               PORT_FreeArena,
+                               PR_FALSE> > ScopedPLArenaPool;
 
 }  // namespace crypto