Add 'Updated just now' timestamp to the Previews infobar

chrome/browser/previews/previews_infobar_tab_helper.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PREVIEWS_PREVIEWS_INFOBAR_TAB_HELPER_H_
 #define CHROME_BROWSER_PREVIEWS_PREVIEWS_INFOBAR_TAB_HELPER_H_
 
 #include "base/macros.h"
 #include "base/optional.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.h"
@@ skipping 13 matching lines @@
     return displayed_preview_infobar_;
   }
 
   // Sets whether the InfoBar for a preview has been shown for the page.
   // |displayed_preview_infobar_| is reset to false on
   // DidStartProvisionalLoadForFrame for the main frame.
   void set_displayed_preview_infobar(bool displayed) {
     displayed_preview_infobar_ = displayed;
   }
 
+  // Sets whether the timestamp on the InfoBar for a preview has been shown for
+  // the page. |displayed_preview_timestamp_| is reset to false on
+  // DidStartProvisionalLoadForFrame for the main frame.
+  void set_displayed_preview_timestamp(bool displayed_preview_timestamp) {
+    displayed_preview_timestamp_ = displayed_preview_timestamp;
+  }
+
   // The data saver page identifier of the current page load.
   const base::Optional<data_reduction_proxy::NavigationID>&
   committed_data_saver_navigation_id() {
     return committed_data_saver_navigation_id_;
   }
 
  private:
   friend class content::WebContentsUserData<PreviewsInfoBarTabHelper>;
   friend class PreviewsInfoBarTabHelperUnitTest;
 
   explicit PreviewsInfoBarTabHelper(content::WebContents* web_contents);
 
   // Clears the last navigation from this tab in the pingback client.
   void ClearLastNavigationAsync() const;
 
   // Overridden from content::WebContentsObserver:
   void DidFinishNavigation(
       content::NavigationHandle* navigation_handle) override;
 
   // Stored for use in the destructor.
   content::BrowserContext* browser_context_;
 
   // True if the InfoBar for a preview has been shown for the page.
   bool displayed_preview_infobar_;
 
+  // True if the InfoBar with a timestamp was shown for the page.
+  bool displayed_preview_timestamp_;
+
   // The data saver page identifier of the current page load.
   base::Optional<data_reduction_proxy::NavigationID>
       committed_data_saver_navigation_id_;
 
   DISALLOW_COPY_AND_ASSIGN(PreviewsInfoBarTabHelper);
 };
 
 #endif  // CHROME_BROWSER_PREVIEWS_PREVIEWS_INFOBAR_TAB_HELPER_H_