Fail the SPDY transaction if it does not meet TLS base requirements.

net/ssl/ssl_cipher_suite_names.h

Index: net/ssl/ssl_cipher_suite_names.h
diff --git a/net/ssl/ssl_cipher_suite_names.h b/net/ssl/ssl_cipher_suite_names.h
index 5145fb24c5ee1393511b3c1ca0f5f40741a39349..1004f43055781b9d87d4a12efb214a387c7fcdfe 100644
--- a/net/ssl/ssl_cipher_suite_names.h
+++ b/net/ssl/ssl_cipher_suite_names.h
@@ -46,6 +46,13 @@ NET_EXPORT void SSLVersionToString(const char** name, int ssl_version);
 NET_EXPORT bool ParseSSLCipherString(const std::string& cipher_string,
                                      uint16* cipher_suite);
 
+// |cipher_suite| is the IANA id for the cipher suite. What a "modern"
+// cipher suite is arbitrarily determined here. The intent is to indicate what
+// cipher suites meet modern security standards when backwards compatibility can
+// be ignored. Notably, HTTP/2 requires/encourages this sort of validation of
+// cipher suites: https://http2.github.io/http2-spec/#TLSUsage.
+bool IsModernTLSCipherSuite(uint16 cipher_suite);
+
 }  // namespace net
 
 #endif  // NET_SSL_SSL_CIPHER_SUITE_NAMES_H_