Add login screen locale and input method device policies

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 121 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: 360
+#   For your editing convenience: highest ID currently used: 362
 #   And don't forget to also update the EnterprisePolicies enum of
 #   histograms.xml.
 #
 # 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 9288 matching lines @@
       The policy should be speicified as a string that expresses the URL and hash in JSON format, e.g.,
       {
         "url": "https://example.com/device_wallpaper.jpg",
         "hash": "examplewallpaperhash"
       }
 
       If the device wallpaper policy is set, the Chrome OS device will download and use the wallpaper image on the login screen if no user has yet signed in to the device. Once the user logs in, the user's wallpaper policy kicks in.
 
       If the device wallpaper policy is left not set, it's the user's wallpaper policy to decide what to show if the user's wallpaper policy is set.''',
     },
+    {
+      'name': 'DeviceLoginScreenLocales',
+      'type': 'list',
+      'schema': {
+        'type': 'array',
+        'items': { 'type': 'string' },
+      },
+      'supported_on': ['chrome_os:58-'],
+      'device_only': True,
+      'features': {
+        'dynamic_refresh': False,
+      },
+      'example_value': [ "en-US" ],
+      'max_size': 16777216,
+      'id': 361,
+      'caption': '''Device sign-in screen locale''',
+      'tags': [],
+      'desc': '''Configures the locale which is enforced on the sign-in screen.''',

[pastarmovj, 2017/01/25 15:42:20]

Please extend the documentation a little bit more. E.g. what happens when this
policy is not set. What happens if the locale is not correct etc. Also this
descriptions says "the locale" and it is a list so it can be more than one
locale, if only one is respected now but the plan is to support multiple
document this too.

[pmarko, 2017/01/26 12:32:58]

Done.

+    },
+    {
+      'name': 'DeviceLoginScreenInputMethods',
+      'type': 'list',
+      'schema': {
+        'type': 'array',
+        'items': { 'type': 'string' },
+      },
+      'supported_on': ['chrome_os:58-'],
+      'device_only': True,
+      'features': {
+        'dynamic_refresh': True,

[pastarmovj, 2017/01/25 15:42:20]

Is it correct that one is dynamic refresh and the other isn't?

[pmarko, 2017/01/26 12:32:58]

Yes, the reason is that changing locale dynamically is currently only supported
in very special situations (e.g. OOBE before login - the webui needs to support
reload, etc.).
The critical situation is when the login screen is displayed and the
DeviceLoginScreenLocales policy changes.
Currently, nothing happens until you restart the browser (hence dynamic_refresh:
False there).
I thought about re-starting the browser automatically, but after all I think
it's not really worth the added complexity. To do it properly, I would need to
add idle detection to not restart the browser when the user is typing something.

+      },
+      'example_value': [ "xkb:us::en" ],
+      'max_size': 16777216,
+      'id': 362,
+      'caption': '''Device sign-in screen keyboard layouts''',
+      'tags': [],
+      'desc': '''Configures which keyboard layouts are allowed on the sign-in screen.''',

[pastarmovj, 2017/01/25 15:42:20]

Same as above.

[pmarko, 2017/01/26 12:32:58]

Done.

+    },
   ],
   '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': [],
 }