Be strict about requiring ServerKeyExchange.

Missing ServerKeyExchange is handled, but only because it hits an
ERR_R_INTERNAL_ERROR in ssl3_send_client_key_exchange in trying to find the
server ECDH parameters. Be strict about requiring it for ECDHE.

Change-Id: Ifce5b73c8bd14746b8a2185f479d550e9e3f84df
Reviewed-on: https://boringssl-review.googlesource.com/1157
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index 1207e9a..3d3e538 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -200,6 +200,17 @@
 		shouldFail:    true,
 		expectedError: ":UNEXPECTED_MESSAGE:",
 	},
+	{
+		name: "SkipServerKeyExchange",
+		config: Config{
+			CipherSuites: []uint16{TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256},
+			Bugs: ProtocolBugs{
+				SkipServerKeyExchange: true,
+			},
+		},
+		shouldFail:    true,
+		expectedError: ":UNEXPECTED_MESSAGE:",
+	},
 }
 
 func doExchange(tlsConn *Conn, messageLen int) error {