Force chrony restart on config change

We've seen handlers being inconsitently being ignored for some
deployments when we force a handler flush mid-playbook. We'll need to
ensure the config is properly loaded if we want to follow up with
subsequent chronyc application so it's best to always invoke the restart
when the configuration actually changes.

Change-Id: I5292f1b1bd65cef340e1e9742463620effc30d26

tasks/config.yml

@@ -6,6 +6,7 @@
     owner: root
     group: root
     mode: 0644
+  register: chrony_config
   notify: Restart chronyd
 
 - name: Ensure chronyd is running
@@ -13,3 +14,16 @@
     name: "{{ chrony_service_name }}"
     state: "{{ chrony_service_state|default('started') }}"
   when: chrony_manage_service|bool
+
+# ansible sometimes ignores handlers when invoked elsewhere. Since we will
+# likely want to restart chrony after a configuration update, let's do it here
+# always. The handler will still trigger for upgrades/updates later as well.
+# This won't have any effect if chrony_manage_service is set to false.
+# See also https://github.com/ansible/ansible/issues/37512
+- name: Force chronyd restart
+  service:
+    name: "{{ chrony_service_name }}"
+    state: restarted
+  when:
+    - chrony_manage_service|bool
+    - chrony_config.changed