Allow showing pending URL for new tab navigations, but only if safe.

chrome/browser/ui/views/constrained_window_views_browsertest.cc

Index: chrome/browser/ui/views/constrained_window_views_browsertest.cc
diff --git a/chrome/browser/ui/views/constrained_window_views_browsertest.cc b/chrome/browser/ui/views/constrained_window_views_browsertest.cc
index f47c041298783f2f5e714cb249a5555c99585bbb..3902b2120a86c7fba0ef06515ed0e58149a1e48a 100644
--- a/chrome/browser/ui/views/constrained_window_views_browsertest.cc
+++ b/chrome/browser/ui/views/constrained_window_views_browsertest.cc
@@ -17,6 +17,7 @@
 #include "components/web_modal/web_contents_modal_dialog_manager.h"
 #include "components/web_modal/web_contents_modal_dialog_manager_delegate.h"
 #include "content/public/browser/native_web_keyboard_event.h"
+#include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
@@ -331,16 +332,25 @@ IN_PROC_BROWSER_TEST_F(ConstrainedWindowViewTest,
       NULL,
       web_contents);
 
+  content::WindowedNotificationObserver back_observer(
+      content::NOTIFICATION_LOAD_STOP,
+      content::Source<content::NavigationController>(
+          &web_contents->GetController()));
   content::RenderViewHost* render_view_host =
       cwdd->GetWebContents()->GetRenderViewHost();
   ForwardKeyEvent(render_view_host, ui::VKEY_BACK);
 
   // Backspace is not processed as accelerator before it's sent to web contents.
+  EXPECT_FALSE(web_contents->GetController().GetPendingEntry());
   EXPECT_EQ(about_url.spec(), web_contents->GetURL().spec());
 
+  // Backspace is processed as accelerator after it's sent to web contents.
   content::RunAllPendingInMessageLoop();
+  EXPECT_TRUE(web_contents->GetController().GetPendingEntry());
 
-  // Backspace is processed as accelerator after it's sent to web contents.
+  // Wait for the navigation to commit, since the URL will not be visible
+  // until then.
+  back_observer.Wait();
   EXPECT_EQ(new_tab_url.spec(), web_contents->GetURL().spec());
 }