Suppress the clang warning "-Wdeprecated-declarations" for CSSM API calls.

net/base/keygen_handler_mac.cc

Index: net/base/keygen_handler_mac.cc
diff --git a/net/base/keygen_handler_mac.cc b/net/base/keygen_handler_mac.cc
index 63ea84751aa1d926cc7fb215edf03d5431567204..4a020bb9776d2903e98a4e2116e5095705fbb2af 100644
--- a/net/base/keygen_handler_mac.cc
+++ b/net/base/keygen_handler_mac.cc
@@ -18,6 +18,11 @@
 #include "crypto/cssm_init.h"
 #include "crypto/mac_security_services_lock.h"
 
+// CSSM functions are deprecated as of OSX 10.7, but have no replacement.
+// https://bugs.chromium.org/p/chromium/issues/detail?id=590914#c1
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+
 // These are in Security.framework but not declared in a public header.
 extern const SecAsn1Template kSecAsn1AlgorithmIDTemplate[];
 extern const SecAsn1Template kSecAsn1SubjectPublicKeyInfoTemplate[];
@@ -322,4 +327,6 @@ static OSStatus SignData(CSSM_DATA data,
   return err;
 }
 
+#pragma clang diagnostic pop  // "-Wdeprecated-declarations"
+
 }  // namespace net