Fix gating job for cookiecutter templates and reclass-system

 * Fix passing of GERRIT_* params, to be able correctly process
   each of jobs in downstream call's

Related-Bug: PROD-23343 (PROD:23343)

Change-Id: I1b3a4610ec91f1d53a4043d282f1b112860c057a
diff --git a/test-system-reclass-pipeline.groovy b/test-system-reclass-pipeline.groovy
index 47dde97..3a3f2f1 100644
--- a/test-system-reclass-pipeline.groovy
+++ b/test-system-reclass-pipeline.groovy
@@ -1,13 +1,15 @@
 def gerrit = new com.mirantis.mk.Gerrit()
 def common = new com.mirantis.mk.Common()
 
+if (env.EXTRA) {
+    common.mergeEnv(env, env.EXTRA)
+}
 
 def slaveNode = env.SLAVE_NODE ?: 'python&&docker'
 def gerritCredentials = env.CREDENTIALS_ID ?: 'gerrit'
 
 def gerritRef = env.GERRIT_REFSPEC ?: null
-def defaultGitRef = env.DEFAULT_GIT_REF ?: null
-def defaultGitUrl = env.DEFAULT_GIT_URL ?: null
+def defaultGitUrl = "${GERRIT_SCHEME}://${GERRIT_NAME}@${GERRIT_HOST}:${GERRIT_PORT}/${GERRIT_PROJECT}"
 
 def checkouted = false
 def merged = false
@@ -28,10 +30,8 @@
                         ])
                         systemRefspec = GERRIT_REFSPEC
                     }
-                    // change defaultGit variables if job triggered from Gerrit
-                    defaultGitUrl = "${GERRIT_SCHEME}://${GERRIT_NAME}@${GERRIT_HOST}:${GERRIT_PORT}/${GERRIT_PROJECT}"
-                } else if (defaultGitRef && defaultGitUrl) {
-                    checkouted = gerrit.gerritPatchsetCheckout(defaultGitUrl, defaultGitRef, "HEAD", gerritCredentials)
+                } else if (gerritRef && defaultGitUrl) {
+                    checkouted = gerrit.gerritPatchsetCheckout(defaultGitUrl, gerritRef, "HEAD", gerritCredentials)
                 }
             }