Add policies to control power management on the Chrome OS login screen

chrome/app/policy/policy_templates.json

Index: chrome/app/policy/policy_templates.json
diff --git a/chrome/app/policy/policy_templates.json b/chrome/app/policy/policy_templates.json
index e06157a89b107c957eafb52502e2f89a85855487..d3b890f3378bbd5f9deb7a31690dba28197fab18 100644
--- a/chrome/app/policy/policy_templates.json
+++ b/chrome/app/policy/policy_templates.json
@@ -112,7 +112,7 @@
 #   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: 223
+#   For your editing convenience: highest ID currently used: 224
 #
 # Placeholders:
 #   The following placeholder strings are automatically substituted:
@@ -4493,6 +4493,92 @@
       ],
     },
     {
+      'name': 'DeviceLoginScreenPowerManagement',
+      'type': 'string',
+      'schema': { 'type': 'string' },
+      'supported_on': ['chrome_os:30-'],
+      'device_only': True,
+      'features': {
+        'dynamic_refresh': True,
+      },
+      'example_value': '{ "AC": { "IdleAction": 3 }, "Battery": { "IdleAction": 3 } }',
+      'id': 224,
+      'caption': '''Power mangement on the login screen''',
+      'desc': '''Configure power management on the login screen in <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph>.
+
+      This policy lets you configure how <ph name="PRODUCT_OS_NAME">$2<ex>Google Chrome OS</ex></ph> behaves when there is no user activity for some amount of time while the login screen is being shown. The policy controls multiple settings. For their individual semantics and value ranges, see the corresponding policies that control power management within a session. The only deviations from these policies are:

[Mattias Nissler (ping if slow), 2013/07/08 17:36:57]

Are we planning on redoing the session power policies to be a dictionary as
well? If so, you'll have to write a full description eventually ;)

[bartfab (slow), 2013/07/09 10:02:33]

Yes, at that point, I will just consolidate the descriptions of the individual
policies into a single description. For now, we need to keep the individual
policies documented. I do not think that duplicating the documentation here
would be very useful.

+      * The actions to take on idle or lid close cannot be to end the session.
+      * The default action taken on idle when running on AC power is to shut down.
+
+      The policy should be specified as a string that expresses the individual settings in JSON format, conforming to the following schema:

[Mattias Nissler (ping if slow), 2013/07/08 17:36:57]

Did you check with Joao what the story is on dictionary-valued policy? I assume
the plan is to go with string for now and switch over to a proper schema here
once end-to-end support for dictionary types becomes available?

It might be helpful to add a TODO here providing some context.

[bartfab (slow), 2013/07/09 10:02:33]

I added a TODO. And yes, I had checked with Joao. His recommendation is to go
with 'string' for now. Once 'dict' is fully supported, it will be trivial to
switch to that as the cloud wire protocol will remain the same - a 'dict' will
still be expressed as a JSON string in the protobuf.

+      {
+        "type": "object",
+        "properties": {
+          "AC": {
+            "type": "object",
+            "properties": {
+              "Delays": {
+                "type": "object",
+                "properties": {
+                  "ScreenDim": {
+                    "type": "integer",
+                    "minimum": 0
+                  },
+                  "ScreenOff": {
+                    "type": "integer",
+                    "minimum": 0
+                  },
+                  "Idle": {
+                    "type": "integer",
+                    "minimum": 0
+                  }
+                }
+              },
+              "IdleAction": {
+                "enum": [ 0, 2, 3 ]

[Mattias Nissler (ping if slow), 2013/07/08 17:36:57]

This seems unfortunate. Can we do a string enum instead?

[bartfab (slow), 2013/07/09 10:02:33]

Done.

+              }
+            }
+          },
+          "Battery": {
+            "type": "object",
+            "properties": {
+              "Delays": {
+                "type": "object",
+                "properties": {
+                  "ScreenDim": {
+                    "type": "integer",
+                    "minimum": 0
+                  },
+                  "ScreenOff": {
+                    "type": "integer",
+                    "minimum": 0
+                  },
+                  "Idle": {
+                    "type": "integer",
+                    "minimum": 0
+                  }
+                }
+              },
+              "IdleAction": {
+                "enum": [ 0, 2, 3 ]

[Mattias Nissler (ping if slow), 2013/07/08 17:36:57]

ditto

[bartfab (slow), 2013/07/09 10:02:33]

Done.

+              }
+            }
+          },
+          "LidCloseAction": {
+            "enum": [ 0, 2, 3 ]

[Mattias Nissler (ping if slow), 2013/07/08 17:36:57]

ditto

[bartfab (slow), 2013/07/09 10:02:33]

Done.

+          },
+          "UserActivityScreenDimDelayScale": {
+            "type": "integer",
+            "minimum": 0
+          }
+        }
+      }
+
+      If a setting is left unspecified, a default value is used.
+
+      If this policy is unset, defaults are used for all settings.''',
+    },
+    {
       'name': 'DeviceAllowRedeemChromeOsRegistrationOffers',
       'type': 'main',
       'schema': { 'type': 'boolean' },