Add timestamp support to the Previews infobar

components/infobars/core/infobar_delegate.h

Index: components/infobars/core/infobar_delegate.h
diff --git a/components/infobars/core/infobar_delegate.h b/components/infobars/core/infobar_delegate.h
index c041844b9d474bbe454287e75e9d6fcbf09b4e52..52bacb321f1125af8a5a7522aec082581d65e370 100644
--- a/components/infobars/core/infobar_delegate.h
+++ b/components/infobars/core/infobar_delegate.h
@@ -16,6 +16,7 @@ class InsecureContentInfoBarDelegate;
 class NativeAppInfoBarDelegate;
 class PermissionInfoBarDelegate;
 class PopupBlockedInfoBarDelegate;
+class PreviewsInfoBarDelegate;
 class RegisterProtocolHandlerInfoBarDelegate;
 class ScreenCaptureInfoBarDelegate;
 class ThemeInstalledInfoBarDelegate;
@@ -219,6 +220,7 @@ class InfoBarDelegate {
   virtual NativeAppInfoBarDelegate* AsNativeAppInfoBarDelegate();
   virtual PermissionInfoBarDelegate* AsPermissionInfoBarDelegate();
   virtual PopupBlockedInfoBarDelegate* AsPopupBlockedInfoBarDelegate();
+  virtual PreviewsInfoBarDelegate* AsPreviewsInfoBarDelegate();
   virtual RegisterProtocolHandlerInfoBarDelegate*
       AsRegisterProtocolHandlerInfoBarDelegate();
   virtual ScreenCaptureInfoBarDelegate* AsScreenCaptureInfoBarDelegate();