[Extensions API] Remove inline enums

chrome/common/extensions/api/system_private.json

Index: chrome/common/extensions/api/system_private.json
diff --git a/chrome/common/extensions/api/system_private.json b/chrome/common/extensions/api/system_private.json
index ea9ae38f8975d3cba6f9985dbe252951bf63b309..4f00e07b7ae97f4b259c6647fb895f3a1860cc5b 100644
--- a/chrome/common/extensions/api/system_private.json
+++ b/chrome/common/extensions/api/system_private.json
@@ -8,14 +8,25 @@
     "description": "none",
     "types": [
       {
+        "id": "UpdateStatusState",
+        "type": "string",
+        "enum": ["NotAvailable", "Updating", "NeedRestart"],
+        "description": "State of system update.  NotAvailable when there is no available update or the update system is in error state, Updating when a system update is in progress, NeedRestart when a system update is finished and restart is needed."
+      },
+      {
+        "id": "GetIncognitoModeAvailabilityValue",
+        "type": "string",
+        "enum": ["enabled", "disabled", "forced"],
+        "description": "Exposes whether the incognito mode is available to windows. One of 'enabled', 'disabled' (user cannot browse pages in Incognito mode), 'forced' (all pages/sessions are forced into Incognito mode)."
+      },
+      {
         "id": "UpdateStatus",
         "type": "object",
         "description": "Information about the system update.",
         "properties": {
           "state": {
-            "type": "string",
-            "enum": ["NotAvailable", "Updating", "NeedRestart"],
-            "description": "State of system update.  NotAvailable when there is no available update or the update system is in error state, Updating when a system update is in progress, NeedRestart when a system update is finished and restart is needed."
+            "$ref": "UpdateStatusState",
+            "description": "State of system update."
           },
           "downloadProgress": {
             "type": "number",
@@ -61,9 +72,7 @@
             "parameters": [
               {
                 "name": "value",
-                "type": "string",
-                "enum": ["enabled", "disabled", "forced"],
-                "description": "Exposes whether the incognito mode is available to windows. One of 'enabled', 'disabled' (user cannot browse pages in Incognito mode), 'forced' (all pages/sessions are forced into Incognito mode)."
+                "$ref": "GetIncognitoModeAvailabilityValue"
               }
             ]
           }