Add getGlobalPolicy to networkingPrivate API.

extensions/browser/api/networking_private/networking_private_delegate.h

Index: extensions/browser/api/networking_private/networking_private_delegate.h
diff --git a/extensions/browser/api/networking_private/networking_private_delegate.h b/extensions/browser/api/networking_private/networking_private_delegate.h
index 78ebc32eaf77cbfa3b90d5f537050092584ea948..1e048b1dc87e315b74866a79b47143ad5eb0af39 100644
--- a/extensions/browser/api/networking_private/networking_private_delegate.h
+++ b/extensions/browser/api/networking_private/networking_private_delegate.h
@@ -164,7 +164,6 @@ class NetworkingPrivateDelegate : public KeyedService {
                                  const std::string& puk,
                                  const VoidCallback& success_callback,
                                  const FailureCallback& failure_callback) = 0;
-
   virtual void SetCellularSimState(const std::string& guid,
                                    bool require_pin,
                                    const std::string& current_pin,
@@ -180,6 +179,12 @@ class NetworkingPrivateDelegate : public KeyedService {
   // Returns a list of DeviceStateProperties.
   virtual std::unique_ptr<DeviceStateList> GetDeviceStateList() = 0;
 
+  // Returns a dictionary of global policy values (may be empty). Note: the
+  // dictionary is expected to be a superset of the networkingPrivate
+  // GlobalPolicy dictionary. Any properties not in GlobalPolicy will be
+  // ignored.
+  virtual std::unique_ptr<base::DictionaryValue> GetGlobalPolicy() = 0;

[Devlin, 2017/01/10 15:25:22]

It looks like this is only used in the new API function, which only needs it to
get a const&.  Can we return a const DictionaryValue* to avoid the copy?

[stevenjb, 2017/01/10 17:49:39]

I guess my main objections to passing const DictionaryValue* is that it would be
inconsistent with the other delegate methods. Also, if we later merge properties
from other sources in the future, the delegate code becomes slightly awkward.

[Devlin, 2017/01/10 18:43:06]

Most other methods actually *do* create/modify the result, so it makes sense to
return a unique_ptr.  Here, we don't.  And if we later merge properties, then we
can adjust the signature again. :)

[stevenjb, 2017/01/10 18:58:29]

How strongly do you feel about this?

+
   // Returns true if the ONC network type |type| is enabled.
   virtual bool EnableNetworkType(const std::string& type) = 0;