Fix tabs duplication when restoring last closed window.

chrome/browser/sessions/session_service.cc

Index: chrome/browser/sessions/session_service.cc
diff --git a/chrome/browser/sessions/session_service.cc b/chrome/browser/sessions/session_service.cc
index 805e03e146f575a2e9ebcf468c8b3a658e37f0b0..3bbb27db5cd6202824a8480ee8f901f80ca82933 100644
--- a/chrome/browser/sessions/session_service.cc
+++ b/chrome/browser/sessions/session_service.cc
@@ -34,6 +34,7 @@
 #include "chrome/browser/sessions/session_restore.h"
 #include "chrome/browser/sessions/session_service_utils.h"
 #include "chrome/browser/sessions/session_tab_helper.h"
+#include "chrome/browser/sessions/tab_restore_service_factory.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/browser_window.h"
@@ -43,6 +44,7 @@
 #include "components/sessions/core/session_command.h"
 #include "components/sessions/core/session_constants.h"
 #include "components/sessions/core/session_types.h"
+#include "components/sessions/core/tab_restore_service.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_details.h"
@@ -588,7 +590,10 @@ bool SessionService::RestoreIfNecessary(const std::vector<GURL>& urls_to_open,
     }
     SessionStartupPref pref = StartupBrowserCreator::GetSessionStartupPref(
         *base::CommandLine::ForCurrentProcess(), profile());
-    if (pref.type == SessionStartupPref::LAST) {
+    sessions::TabRestoreService* tab_restore_service =
+        TabRestoreServiceFactory::GetForProfileIfExisting(profile());
+    if (pref.type == SessionStartupPref::LAST &&
+        (!tab_restore_service || !tab_restore_service->IsRestoring())) {
       SessionRestore::RestoreSession(
           profile(), browser,
           browser ? 0 : SessionRestore::ALWAYS_CREATE_TABBED_BROWSER,