Allow Signin page to open other chrome:// URLs if login content in <webview>

chrome/browser/chrome_content_browser_client.cc

 // 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.
 
 #include "chrome/browser/chrome_content_browser_client.h"
 
 #include <set>
 #include <utility>
 #include <vector>
 
@@ skipping 1035 matching lines @@
   GURL from_url = site_instance->GetSiteURL();
 
 #if defined(ENABLE_EXTENSIONS)
   bool result;
   if (ChromeContentBrowserClientExtensionsPart::ShouldAllowOpenURL(
       site_instance, from_url, url, &result))
     return result;
 #endif
 
   // Do not allow chrome://chrome-signin navigate to other chrome:// URLs, since
-  // the signin page may host untrusted web content.
-  if (from_url.GetOrigin().spec() == chrome::kChromeUIChromeSigninURL &&
+  // the signin page may host untrusted web content when <webview>-based signin
+  // is not enabled. In the <webview> case, untrusted content is out-of-process
+  // and cannot navigate to chrome:// URLs.
+  if (!switches::IsEnableWebviewBasedSignin() &&

[Charlie Reis, 2015/02/04 22:02:57]

I'm still hesitant to change this.  It sounds like it's not necessary for fixing
the bug (since Language Settings will go straight to OpenURLFromTab and not
through here), while inline_login.js continues to route any newwindow events
from the webview (if any) through here.

Why do we need to skip the check?  And do we still need onNewWindow in
inline_login.js?

+      from_url.GetOrigin().spec() == chrome::kChromeUIChromeSigninURL &&
       url.SchemeIs(content::kChromeUIScheme) &&
       url.host() != chrome::kChromeUIChromeSigninHost) {
     VLOG(1) << "Blocked navigation to " << url.spec() << " from "
             << chrome::kChromeUIChromeSigninURL;
     return false;
   }
 
   return true;
 }
 
@@ skipping 1596 matching lines @@
       switches::kDisableWebRtcEncryption,
     };
     to_command_line->CopySwitchesFrom(from_command_line,
                                       kWebRtcDevSwitchNames,
                                       arraysize(kWebRtcDevSwitchNames));
   }
 }
 #endif  // defined(ENABLE_WEBRTC)
 
 }  // namespace chrome