Add SignatureVerifier::VerifyInitRSAPSS for verifying RSA-PSS signatures.

crypto/third_party/nss/chromium-nss.h

Index: crypto/third_party/nss/chromium-nss.h
===================================================================
--- crypto/third_party/nss/chromium-nss.h	(revision 208575)
+++ crypto/third_party/nss/chromium-nss.h	(working copy)
@@ -39,11 +39,20 @@
 
 // This file contains some functions we borrowed from NSS.
 
+#include <prtypes.h>
+#include <hasht.h>
 #include <keyhi.h>
 #include <secmod.h>
 
 #include "crypto/crypto_export.h"
 
+extern "C" SECStatus emsa_pss_verify(const unsigned char *mHash,
+                                     const unsigned char *em,
+                                     unsigned int emLen,
+                                     HASH_HashType hashAlg,
+                                     HASH_HashType maskHashAlg,
+                                     unsigned int sLen);
+
 // Like PK11_ImportEncryptedPrivateKeyInfo, but hardcoded for EC, and returns
 // the SECKEYPrivateKey.
 // See https://bugzilla.mozilla.org/show_bug.cgi?id=211546