Fix user agent override restore pipeline

chrome/browser/ui/tab_contents/tab_contents.cc

Index: chrome/browser/ui/tab_contents/tab_contents.cc
diff --git a/chrome/browser/ui/tab_contents/tab_contents.cc b/chrome/browser/ui/tab_contents/tab_contents.cc
index 3c4a81fe08186078f3d6e461b76bc0f5984172e3..cdfd0eb2ebd6835cfce066e1b3f9d9409309c5e7 100644
--- a/chrome/browser/ui/tab_contents/tab_contents.cc
+++ b/chrome/browser/ui/tab_contents/tab_contents.cc
@@ -28,6 +28,8 @@
 #include "chrome/browser/printing/print_view_manager.h"
 #include "chrome/browser/safe_browsing/safe_browsing_tab_observer.h"
 #include "chrome/browser/sessions/restore_tab_helper.h"
+#include "chrome/browser/sessions/session_service.h"
+#include "chrome/browser/sessions/session_service_factory.h"
 #include "chrome/browser/tab_contents/navigation_metrics_recorder.h"
 #include "chrome/browser/tab_contents/tab_contents_ssl_helper.h"
 #include "chrome/browser/tab_contents/thumbnail_generator.h"
@@ -251,3 +253,15 @@ void TabContents::WebContentsDestroyed(WebContents* tab) {
   // will attempt to access the WebContents and we'll crash.
   DCHECK(in_destructor_);
 }
+
+void TabContents::SetUserAgentOverride(const std::string& user_agent) {
+#if defined(ENABLE_SESSION_SERVICE)
+  SessionService* session =
+      SessionServiceFactory::GetForProfile(profile());
+  if (session) {
+    session->SetTabUserAgentOverride(restore_tab_helper()->window_id(),
+                                     restore_tab_helper()->session_id(),
+                                     user_agent);
+  }
+#endif
+}