Enable download page action for error page

chrome/browser/net/net_error_tab_helper.h

Index: chrome/browser/net/net_error_tab_helper.h
diff --git a/chrome/browser/net/net_error_tab_helper.h b/chrome/browser/net/net_error_tab_helper.h
index 90ffc5279a37e37c77274b7a44e1215426635b1d..ea85185bae8da589e34a06bdc0da50574be73c21 100644
--- a/chrome/browser/net/net_error_tab_helper.h
+++ b/chrome/browser/net/net_error_tab_helper.h
@@ -52,6 +52,12 @@ class NetErrorTabHelper
     dns_probe_status_snoop_callback_ = dns_probe_status_snoop_callback;
   }
 
+#if BUILDFLAG(ANDROID_JAVA_UI)
+  bool is_showing_download_button_in_error_page() const {
+    return is_showing_download_button_in_error_page_;
+  }
+#endif  // BUILDFLAG(ANDROID_JAVA_
+
   // content::WebContentsObserver implementation.
   void RenderFrameCreated(content::RenderFrameHost* render_frame_host) override;
   void DidStartNavigation(
@@ -80,6 +86,7 @@ class NetErrorTabHelper
 
 #if BUILDFLAG(ANDROID_JAVA_UI)
   void DownloadPageLater();
+  void SetIsShowingDownloadButtonInErrorPage(bool show);
 #endif  // BUILDFLAG(ANDROID_JAVA_UI)
 
  private:
@@ -116,6 +123,11 @@ class NetErrorTabHelper
   // is true.  (This should never be true if |dns_error_active_| is false.)
   bool dns_error_page_committed_;
 
+#if BUILDFLAG(ANDROID_JAVA_UI)
+  // True if download button is being shown in the error page.
+  bool is_showing_download_button_in_error_page_;
+#endif  // BUILDFLAG(ANDROID_JAVA_UI
+
   // The status of a DNS probe that may or may not have started or finished.
   // Since the renderer can change out from under the helper (in cross-process
   // navigations), it re-sends the status whenever an error page commits.