Define EnabledComponentUpdates group policy for the component updater.

components/policy/resources/policy_templates.json

Index: components/policy/resources/policy_templates.json
diff --git a/components/policy/resources/policy_templates.json b/components/policy/resources/policy_templates.json
index 1a3c36c9f5f642f0589c8ffb48c6cbc22bf8f82c..3c6acbc027a17cd1502a1816bfc8f3322ade84c7 100644
--- a/components/policy/resources/policy_templates.json
+++ b/components/policy/resources/policy_templates.json
@@ -137,7 +137,7 @@
 #   persistent IDs for all fields (but not for groups!) are needed. These are
 #   specified by the 'id' keys of each policy. NEVER CHANGE EXISTING IDs,
 #   because doing so would break the deployed wire format!
-#   For your editing convenience: highest ID currently used: 341
+#   For your editing convenience: highest ID currently used: 342
 #
 # Placeholders:
 #   The following placeholder strings are automatically substituted:
@@ -8846,6 +8846,32 @@
       },
       'example_value': 'com.android.chrome.SupervisedUserProvider'
     },
+    {
+      'name': 'ComponentUpdates',

[pastarmovj, 2016/08/22 11:30:45]

nit: Remove the group for now. I think we don't need a group for one policy
only. Shall we add more we can always add the group as it has no representation
in the GPO but only in the policy editor UI so we can always reconsider this
decision.

[Sorin Jianu, 2016/08/22 17:35:55]

Done.

+      'type': 'group',
+      'caption': '''Configure component update options.''',
+      'desc': '''These policies affect the behavior of the component updater in <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph>.''',
+      'policies': [
+        {
+          'name': 'ComponentUpdatesEnabled',
+          'type': 'main',
+          'schema': { 'type': 'boolean' },
+          'supported_on': ['chrome.*:54-', 'chrome_os:54-'],
+          'features': {
+            'dynamic_refresh': False,
+            'per_profile': False,
+          },
+          'example_value': True,
+          'id': 342,
+          'caption': '''Enables component updates in <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph>.''',
+          'tags': [],
+          'desc': '''Enables component updates for all components in <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> when not set or set to True.
+
+          If set to False, updates to components are disabled. However, some components are exempt from this policy: updates to any component that does not contain executable code or does not significantly alter the behavior of the browser will not be disabled.

[pastarmovj, 2016/08/22 11:30:45]

nit: if you wish to further justify this decision you can also add "does not
significantly alter the behavior of the browser...and are critical for its
security" (or some such) which is true for both examples below.

[Sorin Jianu, 2016/08/22 17:35:55]

Done.

+          Examples of such components include the certificate revocation lists and safe browsing data. ''',
+        },
+      ],
+    },
   ],
   'messages': {
     # Messages that are not associated to any policies.