Updating onos-buck-gerrit job

- Adding Gerrit trigger
- Updating SCM block to use explicit values (instead of variables)

Change-Id: I1d5bffc55b2bf89e92947278ac034642d3dac2ed
diff --git a/jjb/onos/onos-buck-gerrit.yaml b/jjb/onos/onos-buck-gerrit.yaml
index 46401e8..eda15b0 100644
--- a/jjb/onos/onos-buck-gerrit.yaml
+++ b/jjb/onos/onos-buck-gerrit.yaml
@@ -10,24 +10,36 @@
       script-path: tools/build/jenkins/onos-buck-gerrit
       scm:
         - lf-infra-gerrit-scm:
-            git-url: '$GIT_URL/onos'
-            refspec: 'master'
-            branch: 'master'
-            submodule-recursive: '{submodule-recursive}'
+            git-url: '$GIT_URL/$PROJECT'
+            refspec: '$GERRIT_REFSPEC'
+            branch: '$GERRIT_BRANCH'
+            #submodule-recursive: '{submodule-recursive}'
+            submodule-recursive: false
             choosing-strategy: gerrit
-            jenkins-ssh-credential: '{jenkins-ssh-credential}'
+            #jenkins-ssh-credential: '{jenkins-ssh-credential}'
+            jenkins-ssh-credential: 'jenkins'
+            shallow-clone: true
 
-#    triggers:
-#      - gerrit:
-#          server-name: '{gerrit-server-name}'
-#          trigger-on: '{obj:gerrit_verify_triggers}'
-#          projects:
-#            - project-compare-type: ANT
-#              project-pattern: '{project}'
-#              branches:
-#                - branch-compare-type: ANT
-#                  branch-pattern: '**/{branch}'
-#              file-paths: '{obj:gerrit_trigger_file_paths}'
+    triggers:
+      - gerrit:
+          #server-name: '{gerrit-server-name}'
+          server-name: 'ONOS Project Gerrit'
+          #trigger-on: '{obj:gerrit_verify_triggers}'
+          trigger-on:
+            - patchset-created-event:
+                exclude-drafts: true
+                exclude-trivial-rebase: false
+                exclude-no-code-change: true
+            - draft-published-event
+          projects:
+            - project-compare-type: PLAIN
+              #project-pattern: '{project}'
+              project-pattern: 'onos'
+              branches:
+                - branch-compare-type: ANT
+                  #branch-pattern: '**/{branch}'
+                  branch-pattern: '**/master'
+              #file-paths: '{obj:gerrit_trigger_file_paths}'
 
 - project:
     name: onos-buck-gerrit