Policy implementation for encryptfs to ext4 migration strategy

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 125 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: 373
+#   For your editing convenience: highest ID currently used: 374
 #   And don't forget to also update the EnterprisePolicies enum of
 #   histograms.xml (run 'python tools/metrics/histograms/update_policies.py').
 #
 # 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
 #
@@ skipping 9532 matching lines @@
       'example_value': False,
       'id': 373,
       'caption': '''Use System Default Printer as Default''',
       'tags': [],
       'desc': '''Causes <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> to use the system default printer as the default choice in Print Preview instead of the most recently used printer.
 
       If you disable this setting or do not set a value, Print Preview will use the most recently used printer as the default destination choice.
 
       If you enable this setting, Print Preview will use the OS system default printer as the default destination choice.''',
     },
+    {
+      'name': 'DeviceEcryptfsMigrationStrategy',
+      'type': 'int-enum',
+      'schema': {
+        'type': 'integer',
+        'enum': [ 0, 1, 2 ],
+      },
+      'items': [
+        {
+          'name': 'Unset',
+          'value': 0,
+          'caption': '''Policy unset, disallow data migration and ARC''',
+        },
+        {
+          'name': 'DisallowArc',
+          'value': 1,
+          'caption': '''Disallow data migration and ARC''',
+        },
+        {
+          'name': 'AllowMigration',
+          'value': 2,
+          'caption': '''Allow data migration''',
+        },
+      ],
+      'supported_on': ['chrome_os:60-'],
+      'device_only': True,
+      'features': {
+        'dynamic_refresh': True,
+      },
+      'example_value': 1,
+      'id': 374,
+      'caption': '''Migration strategy for ecryptfs''',
+      'tags': [],
+      'desc': '''Specifies how a device should behave that shipped with ecryptfs and needs to transition to ext4 encryption.
+
+      If you set this policy to 'DisallowArc', Android apps will be disabled for all users on the device (including those that have ext4 encryption already) and no migration from ecryptfs to ext4 encryption will be offered to any users.
+
+      If you set this policy to 'AllowMigration', users with ecryptfs home directories will be offered to migrate these to ext4 encryption as necessary (currently when Android N becomes available on the device).
+
+      If this policy is left not set, the device will behave as if 'DisallowArc' was chosen.''',
+    },
   ],
   '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 113 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': [],
 }