Added the SuppressUnsupportedOSWarning policy setting.

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: 323
+#   For your editing convenience: highest ID currently used: 324
 #
 # 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 8201 matching lines @@
       'example_value': True,
       'id': 323,
       'caption': '''Allow bluetooth on device''',
       'tags': [],
       'desc': '''If this policy is set to false, <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph> will disable Bluetooth and the user cannot enable it back.
 
       If this policy is set to true or left unset, the user will be able to enable or disable Bluetooth as he wishes.
 
       If this policy is set, the user cannot change or override it.''',
     },
+    {
+      'name': 'SuppressUnsupportedOSWarning',
+      'caption': '''Suppress the unsupported OS warning''',
+      'desc': '''Suppresses the warning that appears when <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> is running on a computer or operating system that is no longer supported.''',
+      'type': 'main',
+      'schema': { 'type': 'boolean' },
+      'supported_on': ['chrome.*:49-','chrome_os:49-'],

[Thiemo Nagel, 2016/03/30 16:13:03]

Does that really apply to Chrome OS?  Under which circumstance do we currently
display unsupported OS warnings on Chrome OS?

+      'features': {
+        'dynamic_refresh': False,
+        'per_profile': False,
+      },
+      'example_value': True,
+      'tags': ['system-security'],
+      'id': 324,
+    },
   ],
   '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': [],
 }