Do not update url of Chrome signin page for the inital and continue page

chrome/browser/resources/gaia_auth/main.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * Authenticator class wraps the communications between Gaia and its host.
  */
 function Authenticator() {
 }
 
@@ skipping 76 matching lines @@
     if (this.inputLang_)
       url = appendParam(url, 'hl', this.inputLang_);
     if (this.inputEmail_)
       url = appendParam(url, 'Email', this.inputEmail_);
 
     return url;
   },
 
   /** Callback when all loads in the gaia webview is complete. */
   onWebviewLoadstop_: function(gaiaFrame) {
-    // Report the current state to the parent which will then update the
-    // browser history so that later it could respond properly to back/forward.
-    var msg = {
-      'method': 'reportState',
-      'src': gaiaFrame.src
-    };
-    window.parent.postMessage(msg, this.parentPage_);
-
-    if (gaiaFrame.src.lastIndexOf(
-        this.continueUrlWithoutParams_, 0) == 0) {
+    if (gaiaFrame.src.lastIndexOf(this.continueUrlWithoutParams_, 0) == 0) {
       // Detect when login is finished by the load stop event of the continue
       // URL. Cannot reuse the login complete flow in success.html, because
       // webview does not support extension pages yet.
       var skipForNow = false;
       if (this.inlineMode_ && gaiaFrame.src.indexOf('ntp=1') >= 0) {
         skipForNow = true;
       }
       msg = {
         'method': 'completeLogin',
         'skipForNow': skipForNow
       };
       window.parent.postMessage(msg, this.parentPage_);
+      // Do no report state to the parent for the continue URL, since it is a
+      // blank page.
       return;
     }
 
+    // Report the current state to the parent which will then update the
+    // browser history so that later it could respond properly to back/forward.
+    var msg = {
+      'method': 'reportState',
+      'src': gaiaFrame.src
+    };
+    window.parent.postMessage(msg, this.parentPage_);
+
     if (gaiaFrame.src.lastIndexOf(this.gaiaUrl_, 0) == 0) {
       gaiaFrame.executeScript({file: 'inline_injected.js'}, function() {
         // Send an initial message to gaia so that it has an JavaScript
         // reference to the embedder.
         gaiaFrame.contentWindow.postMessage('', gaiaFrame.src);
       });
     }
 
     this.loaded_ || this.onLoginUILoaded();
   },
@@ skipping 171 matching lines @@
     } else if (msg.method == 'redirectToSignin' &&
                this.isParentMessage_(e)) {
       $('gaia-frame').src = this.constructInitialFrameUrl_();
     } else {
        console.error('Authenticator.onMessage: unknown message + origin!?');
     }
   }
 };
 
 Authenticator.getInstance().initialize();