Add tests for full handshakes under renegotiation.

In verifying the fix for CVE-2015-0291, I noticed we don't actually have any
test coverage for full handshakes on renegotiation. All our tests always do
resumptions.

Change-Id: Ia9b701e8a50ba9353fefb8cc4fb86e78065d0b40
Reviewed-on: https://boringssl-review.googlesource.com/4050
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/test/runner/common.go b/ssl/test/runner/common.go
index b8cc44a..a33ad19 100644
--- a/ssl/test/runner/common.go
+++ b/ssl/test/runner/common.go
@@ -663,6 +663,10 @@
 	// SendEmptyFragments, if true, causes handshakes to include empty
 	// fragments in DTLS.
 	SendEmptyFragments bool
+
+	// NeverResumeOnRenego, if true, causes renegotiations to always be full
+	// handshakes.
+	NeverResumeOnRenego bool
 }
 
 func (c *Config) serverInit() {