Remove final uses of app.accountReady

Change-Id: I9ed0591d3c0fa673a7bcadbbee0b998b0a57eb05
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
index 190a286..456e983 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
@@ -67,16 +67,14 @@
       Gerrit.RESTClientBehavior,
     ],
 
-    ready: function() {
-      app.accountReady.then(function() {
-        this._loggedIn = app.loggedIn;
-        if (this._loggedIn) {
+    attached: function() {
+      this._getLoggedIn().then(function(loggedIn) {
+        this._loggedIn = loggedIn;
+        if (loggedIn) {
           this._setReviewed(true);
         }
       }.bind(this));
-    },
 
-    attached: function() {
       if (this._path) {
         this.fire('title-change',
             {title: this._computeFileDisplayName(this._path)});
@@ -88,6 +86,10 @@
       window.removeEventListener('resize', this._boundWindowResizeHandler);
     },
 
+    _getLoggedIn: function() {
+      return this.$.restAPI.getLoggedIn();
+    },
+
     _handleReviewedChange: function(e) {
       this._setReviewed(Polymer.dom(e).rootTarget.checked);
     },