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

net/cert/x509_util_mac.cc

Index: net/cert/x509_util_mac.cc
diff --git a/net/cert/x509_util_mac.cc b/net/cert/x509_util_mac.cc
index 3959b80eb4840391a458fa56bb2081b0228fc542..7971a733af07cbc3855ac9e1e649911f47a552bb 100644
--- a/net/cert/x509_util_mac.cc
+++ b/net/cert/x509_util_mac.cc
@@ -9,6 +9,11 @@
 
 namespace net {
 
+// 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"
+
 namespace x509_util {
 
 namespace {
@@ -228,4 +233,6 @@ OSStatus CSSMCachedCertificate::GetField(const CSSM_OID* field_oid,
 
 }  // namespace x509_util
 
+#pragma clang diagnostic pop  // "-Wdeprecated-declarations"
+
 }  // namespace net