test: add hasFipsCrypto to test/common.js

Utility function for tests to check if OpenSSL is using
a FIPS verified cryptographic provider.

PR-URL: https://github.com/nodejs/node/pull/3756
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: Shigeki Ohtsu <ohtsu@iij.ad.jp>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/common.js

@@ -137,9 +137,17 @@ Object.defineProperty(exports, 'opensslCli', {get: function() {
   return opensslCli;
 }, enumerable: true });
 
-Object.defineProperty(exports, 'hasCrypto', {get: function() {
+Object.defineProperty(exports, 'hasCrypto', {
+  get: function() {
     return process.versions.openssl ? true : false;
-}});
+  }
+});
+
+Object.defineProperty(exports, 'hasFipsCrypto', {
+  get: function() {
+    return process.config.variables.openssl_fips ? true : false;
+  }
+});
 
 if (exports.isWindows) {
   exports.PIPE = '\\\\.\\pipe\\libuv-test';