Add support for multiple allowed domains

remoting/host/policy_watcher.h

Index: remoting/host/policy_watcher.h
diff --git a/remoting/host/policy_watcher.h b/remoting/host/policy_watcher.h
index 5523b8478969d01b7c5d80c52896d0b5c0459d3f..44f38638de48f79f85f23d60b513c23587c0d000 100644
--- a/remoting/host/policy_watcher.h
+++ b/remoting/host/policy_watcher.h
@@ -92,12 +92,18 @@ class PolicyWatcher : public policy::PolicyService::Observer,
   // Gets Chromoting schema stored inside |owned_schema_registry_|.
   const policy::Schema* GetPolicySchema() const;
 
-  // Simplifying wrapper around Schema::Normalize.
+  // Normalizes policies using Schema::Normalize and converts deprecated
+  // policies.
+  //
   // - Returns false if |dict| is invalid (i.e. contains mistyped policy
   // values).
   // - Returns true if |dict| was valid or got normalized.
   bool NormalizePolicies(base::DictionaryValue* dict);
 
+  // Converts each deprecated policy to its replacement if and only if the
+  // replacement policy is not set, and removes deprecated policied from dict.
+  void HandleDeprecatedPolicies(base::DictionaryValue* dict);

[pastarmovj, 2017/04/24 13:06:34]

In order to not reinvent the wheel can you try to write a 
LegacyPoliciesDeprecatingPolicyHandler that will do the same thing
https://cs.chromium.org/chromium/src/components/policy/core/browser/configura...
or if this one is too limiting a regular SimplePolicyHandler.

This way you can even completely remove the old prefs in favor of only the new
ones and get the same effect with simpler client code.

[rkjnsn, 2017/04/24 17:20:47]

Unfortunately, I don't believe we can use
LegacyPoliciesDeprecatingPolicyHandler. Chrome Remote Desktop reads and
processes the policy directly, rather than using PolicyHandlers to load them
into prefs.

+
   // Stores |new_policies| into |old_policies_|.  Returns dictionary with items
   // from |new_policies| that are different from the old |old_policies_|.
   std::unique_ptr<base::DictionaryValue> StoreNewAndReturnChangedPolicies(