Define EnabledComponentUpdates group policy for the component updater.

components/policy/resources/policy_templates.json

 {
 # policy_templates.json - Metafile for policy templates
 #
 # The content of this file is evaluated as a Python expression.
 #
 # This file is used as input to generate the following policy templates:
 # ADM, ADMX+ADML, MCX/plist and html documentation.
 #
 # Policy templates are user interface definitions or documents about the
 # policies that can be used to configure Chrome. Each policy is a name-value
@@ skipping 119 matching lines @@
 #   templates and documentation. The policy definition list that Chrome sees
 #   will include policies marked with 'future'. If a WIP policy isn't meant to
 #   be seen by the policy providers either, the 'supported_on' key should be set
 #   to an empty list.
 #
 # IDs:
 #   Since a Protocol Buffer definition is generated from this file, unique and
 #   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:
 #     $1 -> Google Chrome / Chromium
 #     $2 -> Google Chrome OS / Chromium OS
 #     $3 -> Google Chrome Frame / Chromium Frame
 #     $6 is reserved for doc_writer
 #
 # Device Policy:
 #   An additional flag 'device_only' (optional, defaults to False) indicates
@@ skipping 8688 matching lines @@
       'tags': ['filtering'],
       'supported_on': ['webview_android:54-'],
       'caption': '''Set an external source of URL restrictions''',
       'desc' : '''When this policy is set to a non-empty string the WebView will read URL restrictions from the content provider with the given authority name.''',
       'features': {
         'dynamic_refresh': True,
         'per_profile': False,
       },
       '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.
     'win_supported_winxpsp2': {
       'desc': '''A label specifying the oldest possible compatible version of Windows. This text will appear right next to a label containing the text 'Supported on:'.''',
       'text': '''Microsoft Windows XP SP2 or later'''
     },
     'mac_chrome_preferences': {
       'desc': '''A text indicating in Mac OS X Workgroup Manager, that currently the preferences of Chromium are being edited''',
       'text': '''<ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> preferences'''
@@ skipping 109 matching lines @@
       'desc': '''Text appended in parentheses next to the policies top-level container to indicate that those policies are of the Recommended level''',
       'text': 'Default Settings (users can override)',
     },
     'doc_complex_policies_on_windows': {
       'desc': '''Text pointing the user to a help article for complex policies on Windows''',
       'text': '''encoded as a JSON string, for details see <ph name="COMPLEX_POLICIES_URL">https://www.chromium.org/administrators/complex-policies-on-windows<ex>https://www.chromium.org/administrators/complex-policies-on-windows</ex></ph>''',
     },
   },
   'placeholders': [],
 }