chromeos: Refactor ash SystemTrayDelegate enterprise methods to mojo

ash/public/interfaces/system_tray.mojom

Index: ash/public/interfaces/system_tray.mojom
diff --git a/ash/public/interfaces/system_tray.mojom b/ash/public/interfaces/system_tray.mojom
index fc980e88c20b0f3c5ec7a27371eb3c344ae02f90..912bf0477c5701365a195d178223ff880c48f55d 100644
--- a/ash/public/interfaces/system_tray.mojom
+++ b/ash/public/interfaces/system_tray.mojom
@@ -23,6 +23,11 @@ interface SystemTray {
   // Otherwise sets 12 hour time formatting.
   SetUse24HourClock(bool use_24_hour);
 
+  // Sets enterprise management information. If |enterprise_domain| is not empty
+  // or |active_directory_managed| is true then an item will be shown in the
+  // system tray menu stating that the device is managed.
+  SetEnterpriseDomain(string enterprise_domain, bool active_directory_managed);

[Tom Sepez, 2017/04/26 19:29:53]

This just updates the display, right?  No change of status actually occurs?

[James Cook, 2017/04/26 21:04:15]

Correct. I updated the comment to try to clarify.

+
   // Shows an icon in the system tray indicating that a software update is
   // available. Once shown the icon persists until reboot. |severity| and
   // |factory_reset_required| are used to set the icon, color, and tooltip.
@@ -85,7 +90,8 @@ interface SystemTrayClient {
   // Shows information about public account mode.
   ShowPublicAccountInfo();
 
-  // TODO(crbug.com/647412): ShowEnterpriseInfo();
+  // Shows information about enterprise enrolled devices.
+  ShowEnterpriseInfo();
 
   // Shows UI to configure or activate the network specified by |network_id|,
   // which may include showing payment or captive portal UI when appropriate.