Add a new policy to allow for release channel delegation.

chrome/app/policy/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 94 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: 133
+#   For your editing convenience: highest ID currently used: 134
 #
 # 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 1855 matching lines @@
       'example_value': 3600000,
       'id': 90,
       'caption': '''Refresh rate for Device Policy''',
       'desc': '''Specifies the period in milliseconds at which the device management service is queried for device policy information.
 
       Setting this policy overrides the default value of 3 hours. Valid values for this policy are in the range from 1800000 (30 minutes) to 86400000 (1 day). Any values not in this range will be clamped to the respective boundary.
 
       Leaving this policy not set will make <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph> use the default value of 3 hours.''',
     },
     {
-      'name': 'ChromeOsReleaseChannel',
-      'type': 'string-enum',
-      'items': [
-        {
-          'name': 'StableChannel',
-          'value': 'stable-channel',
-          'caption': '''Stable channel'''
-        },
-        {
-          'name': 'BetaChannel',
-          'value': 'beta-channel',
-          'caption': '''Beta channel'''
-        },
-        {
-          'name': 'DevChannel',
-          'value': 'dev-channel',
-          'caption': '''Dev channel (may be unstable)'''
-        }
-      ],
-      'supported_on': ['chrome_os:0.11-'],
-      'device_only': True,
-      'features': {'dynamic_refresh': True},
-      'example_value': 'stable-channel',
-      'id': 91,
-      'caption': '''Release channel''',
-      'desc': '''Specifies the release channel that this device should be locked to.'''
-    },
-    {
       'name': 'ImportBookmarks',
       'type': 'main',
       'supported_on': ['chrome.*:15-'],
       'features': {
         'dynamic_refresh': True,
         'can_be_recommended': True,
       },
       'example_value': True,
       'id': 97,
       'caption': '''Import bookmarks from default browser on first run''',
@@ skipping 375 matching lines @@
       'type': 'main',
       'supported_on': ['chrome_os:14-'],
       'device_only': True,
       'features': {'dynamic_refresh': True},
       'example_value': True,
       'id': 127,
       'caption': '''Enable metrics reporting''',
       'desc': '''Controls whether usage metrics are reported back to Google. If set to true, <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph> will report usage metrics. If not configured or set to false, metrics reporting will be disabled.''',
     },
     {
+      'name': 'ChromeOsReleaseChannel',
+      'type': 'string-enum',
+      'items': [
+        {
+          'name': 'StableChannel',
+          'value': 'stable-channel',
+          'caption': '''Stable channel'''
+        },
+        {
+          'name': 'BetaChannel',
+          'value': 'beta-channel',
+          'caption': '''Beta channel'''
+        },
+        {
+          'name': 'DevChannel',
+          'value': 'dev-channel',
+          'caption': '''Dev channel (may be unstable)'''
+        }
+      ],
+      'supported_on': ['chrome_os:0.11-'],
+      'device_only': True,
+      'features': {'dynamic_refresh': True},
+      'example_value': 'stable-channel',
+      'id': 91,
+      'caption': '''Release channel''',
+      'desc': '''Specifies the release channel that this device should be locked to.'''
+    },
+    {
+      'name': 'ChromeOsReleaseChannelDelegated',
+      'type': 'main',
+      'supported_on': ['chrome_os:0.19-'],
+      'features': {'dynamic_refresh': True},
+      'example_value': False,
+      'id': 134,
+      'caption': '''Wether the release channel should be settable by the user or locked.''',
+      'desc': '''If this policy is set to True and the ChromeOsReleaseChannel policy is not specified the users of the enrolling domain will be allowed to change the release channel of the device. If this policy is set to false the device will be locked in whatever channel it was last set.
+
+      The user selected channel will be overriden by the ChromeOsReleaseChannel policy but if the policy channel is more stable than the one that was installed on the device, channel switch might will only after the version of the more stable channel reaches number higher than the one installed on the device.''',
+    },
+    {
       'name': 'DeviceEphemeralUsersEnabled',
       'type': 'main',
       'supported_on': ['chrome_os:19-'],
       'device_only': True,
       'features': {'dynamic_refresh': True},
       'example_value': True,
       'id': 128,
       'caption': '''Wipe user data on sign-out''',
       'desc': '''Determines whether Chrome OS keeps local account data after logout. If set to true, no persistent accounts are kept by <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph> and all data from the user session will be discarded after logout. If this policy is set to false or not configured, the device may keep (encrypted) local user data.''',
     },
@@ skipping 146 matching lines @@
       'desc': '''Text appended in parentheses to the policy name to indicate that it has been deprecated''',
       'text': 'deprecated',
     },
     'doc_recommended': {
       'desc': '''Text appended in parentheses next to the policies top-level container to indicate that those policies are of the Recommended level''',
       'text': 'Recommended',
     },
   },
   'placeholders': [],
 }