Fix crash when an SSL key-log file couldn't be opened.

net/third_party/nss/patches/sslkeylogerror.patch

Index: net/third_party/nss/patches/sslkeylogerror.patch
diff --git a/net/third_party/nss/patches/sslkeylogerror.patch b/net/third_party/nss/patches/sslkeylogerror.patch
new file mode 100644
index 0000000000000000000000000000000000000000..7dd57c2b0123facd859ec6545ea05757511a8698
--- /dev/null
+++ b/net/third_party/nss/patches/sslkeylogerror.patch
@@ -0,0 +1,24 @@
+diff --git a/net/third_party/nss/ssl/sslsock.c b/net/third_party/nss/ssl/sslsock.c
+index 1823a1c..2a93dae 100644
+--- a/net/third_party/nss/ssl/sslsock.c
++++ b/net/third_party/nss/ssl/sslsock.c
+@@ -2934,11 +2934,15 @@ ssl_SetDefaultsFromEnvironment(void)
+ 	ev = getenv("SSLKEYLOGFILE");
+ 	if (ev && ev[0]) {
+ 	    ssl_keylog_iob = fopen(ev, "a");
+-	    if (ftell(ssl_keylog_iob) == 0) {
+-		fputs("# SSL/TLS secrets log file, generated by NSS\n",
+-		      ssl_keylog_iob);
++	    if (!ssl_keylog_iob) {
++		SSL_TRACE(("Failed to open key log file"));
++	    } else {
++		if (ftell(ssl_keylog_iob) == 0) {
++		    fputs("# SSL/TLS secrets log file, generated by NSS\n",
++			  ssl_keylog_iob);
++		}
++		SSL_TRACE(("SSL: logging pre-master secrets to %s", ev));
+ 	    }
+-	    SSL_TRACE(("SSL: logging pre-master secrets to %s", ev));
+ 	}
+ 	ev = getenv("SSLBYPASS");
+ 	if (ev && ev[0]) {