Allow chrome.loginState API for Smart Card Connector app

The chrome.loginState API was only exposed to Chrome Extensions.

This change exposes this API to the Smart Card Connector, which
is a Chrome App. The Connector app needs this API in order to
fix an issue related to user session states (details on the bug).

Bug: 1034927
Change-Id: I17a3d5fb7446ae65b9ef500011615a20b841c4f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1970311
Commit-Queue: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Cr-Commit-Position: refs/heads/master@{#731786}

chrome/common/extensions/api/_permission_features.json

@@ -481,11 +481,21 @@
       "4DBFC1C52D6660DD90791976DF7FEF7B3D360509"  // Imprivata (login screen) DEV
     ]
   },
-  "loginState": {
-    "channel": "stable",
-    "extension_types": ["login_screen_extension", "extension"],
-    "platforms": ["chromeos"]
-  },
+  "loginState": [
+    {
+      "channel": "stable",
+      "extension_types": ["login_screen_extension", "extension"],
+      "platforms": ["chromeos"]
+    },
+    {
+      "channel": "stable",
+      "extension_types": ["platform_app"],
+      "platforms": ["chromeos"],
+      "whitelist": [
+        "EC3DE21E048B67319893889529354DFBFA96FD23"  // Smart Card Connector
+      ]
+    }
+  ],
   "webcamPrivate": {
     "channel": "stable",
     "extension_types": ["extension", "platform_app"],