Rename enterprise policy proto fields from KIOSK to RETAIL.

chrome/browser/policy/proto/device_management_backend.proto

Index: chrome/browser/policy/proto/device_management_backend.proto
diff --git a/chrome/browser/policy/proto/device_management_backend.proto b/chrome/browser/policy/proto/device_management_backend.proto
index 9db8cc93e3fbd0668ad30b3750113d926d4487bf..b6396020cf0aa21fab52f869a56a905be6d4ae2a 100644
--- a/chrome/browser/policy/proto/device_management_backend.proto
+++ b/chrome/browser/policy/proto/device_management_backend.proto
@@ -38,11 +38,11 @@ message DeviceRegisterRequest {
   // "Android", or "Chrome OS".
   optional string machine_model = 4;
 
-  // When true, indicates that the |machine_id| field should be known to the
-  // server. The server can do additional checks based on this information.
-  // This is currently used for requests triggered by auto-enrollment.
+  // When true, indicates that the |machine_id| has been identified as auto-
+  // enrollment candidate on the client and the server can use it to verify
+  // that the client is to be enrolled in the correct mode.
   // Defaults to false when not present.
-  optional bool known_machine_id = 5;
+  optional bool auto_enrolled = 5;
 }
 
 // Response from server to device register request.
@@ -64,10 +64,10 @@ message DeviceRegisterResponse {
     // controlled through the cloud policy infrastructure. Auto-enrollment is
     // supported in that mode.
     ENTERPRISE = 0;
-    // Devices in KIOSK mode also have no local owner and get their device
+    // Devices in RETAIL mode also have no local owner and get their device
     // settings from the cloud, but additionally this mode enables the demo
     // account on the device.
-    KIOSK = 1;
+    RETAIL = 1;
   }
   optional DeviceMode enrollment_type = 3 [default = ENTERPRISE];
 }