Honour TEMPLATE_BUCKET_NAME variable when deploying load-balancer

Pass TemplateBucketName to service-lb stack, so that task execution role
template is retrieved from the correct S3 bucket.

Bug: Issue 13437
Change-Id: Ic0c6e523016e06ee5967982f09b912c5fdadde9b
diff --git a/dual-master/Makefile b/dual-master/Makefile
index 1921528..8ff1237 100644
--- a/dual-master/Makefile
+++ b/dual-master/Makefile
@@ -256,6 +256,7 @@
 		ParameterKey=GerritKeyPrefix,ParameterValue=$(GERRIT_KEY_PREFIX)\
 		ParameterKey=CertificateArn,ParameterValue=$(SSL_CERTIFICATE_ARN) \
 		ParameterKey=Subdomain,ParameterValue=$(LB_SUBDOMAIN) \
+		ParameterKey=TemplateBucketName,ParameterValue=$(TEMPLATE_BUCKET_NAME) \
 		ParameterKey=HAProxyDockerImage,ParameterValue=aws-gerrit/haproxy:$(HAPROXY_HEAD_SHA1) \
 		ParameterKey=SidecarDockerImage,ParameterValue=aws-gerrit/syslog-sidecar:$(SYSLOG_HEAD_SHA1) \
 		$(REPLICATION_SERVICE_OPTIONAL_PARAMS) \
diff --git a/dual-master/cf-service-lb.yml b/dual-master/cf-service-lb.yml
index 39882ff..257a5e9 100644
--- a/dual-master/cf-service-lb.yml
+++ b/dual-master/cf-service-lb.yml
@@ -8,6 +8,9 @@
       Description: Stack name of the ECS cluster to deploy the services
       Type: String
       Default: gerrit-cluster
+  TemplateBucketName:
+    Description: S3 bucket containing cloudformation templates
+    Type: String
   EnvironmentName:
       Description: An environment name used to build the log stream names
       Type: String
@@ -150,7 +153,7 @@
     ECSTaskExecutionRoleStack:
       Type: AWS::CloudFormation::Stack
       Properties:
-        TemplateURL: https://aws-gerrit-cf-templates.s3.amazonaws.com/cf-gerrit-task-execution-role.yml
+        TemplateURL: !Join [ '', ['https://', !Ref TemplateBucketName, '.s3.amazonaws.com/cf-gerrit-task-execution-role.yml'] ]
         TimeoutInMinutes: '5'
 
     LoadBalancer: