signin: force web signin flow initiated visits to accounts.google.com to their own process.

chrome/browser/ui/webui/sync_promo/sync_promo_ui.h

Index: chrome/browser/ui/webui/sync_promo/sync_promo_ui.h
diff --git a/chrome/browser/ui/webui/sync_promo/sync_promo_ui.h b/chrome/browser/ui/webui/sync_promo/sync_promo_ui.h
index decb4024d08959b7652dc035ca877e5396ae05d3..fa252ee888a1e461b9309fb317b68f7728037ae4 100644
--- a/chrome/browser/ui/webui/sync_promo/sync_promo_ui.h
+++ b/chrome/browser/ui/webui/sync_promo/sync_promo_ui.h
@@ -79,6 +79,10 @@ class SyncPromoUI : public content::WebUIController {
   // Forces UseWebBasedSigninFlow() to return true when set; used in tests only.
   static void ForceWebBasedSigninFlowForTesting(bool force);
 
+  // Returns true if |url| is a web signin URL and should be hosted in an
+  // isolated, privileged signin process.
+  static bool IsWebBasedSigninFlowURL(const GURL& url);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncPromoUI);
 };