Add "SHOW ALL SAVED PAGES" button to offline error page

chrome/common/localized_error.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/common/localized_error.h"
 
 #include "base/command_line.h"
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
@@ skipping 536 matching lines @@
 }  // namespace
 
 const char LocalizedError::kHttpErrorDomain[] = "http";
 
 void LocalizedError::GetStrings(int error_code,
                                 const std::string& error_domain,
                                 const GURL& failed_url,
                                 bool is_post,
                                 bool stale_copy_in_cache,
                                 bool can_show_network_diagnostics_dialog,
+                                bool has_offline_pages,
                                 const std::string& locale,
                                 const std::string& accept_languages,
                                 scoped_ptr<error_page::ErrorPageParams> params,
                                 base::DictionaryValue* error_strings) {
   webui::SetLoadTimeDataDefaults(locale, error_strings);
 
   // Grab the strings and settings that depend on the error type.  Init
   // options with default values.
   LocalizedErrorMap options = {
     0,
@@ skipping 192 matching lines @@
         "msg", l10n_util::GetStringUTF16(
             IDS_ERRORPAGES_BUTTON_SHOW_SAVED_COPY));
     show_saved_copy_button->SetString(
         "title",
         l10n_util::GetStringUTF16(IDS_ERRORPAGES_BUTTON_SHOW_SAVED_COPY_HELP));
     if (show_saved_copy_primary)
       show_saved_copy_button->SetString("primary", "true");
     error_strings->Set("showSavedCopyButton", show_saved_copy_button);
   }
 
+#if defined(OS_ANDROID)
+  if (has_offline_pages) {

[mmenke, 2015/11/05 16:18:12]

One other question:  Should we do this for all errors, or only ones that
indicate we may be offline (ERR_INTERNET_DISCONNECTED is pretty certain, but
then can throw in a could others, where we may just have local connectivity. 
ERR_NAME_NOT_RESOLVED, especially).

[edwardjung, 2015/11/05 17:08:01]

My feeling is that this should be restricted to the offline ones. For some net
errors, a reload might fix the issue. I've seen a proposed layout for how this
looks and it uses the blue button. We generally don't want to the "Show all
saved pages" action to be over an action which might fix the connection issue.  

Selectively showing this link might cause other issues if user learns to expect
to see this button on all net errors. Users will probably not understand our
'offline' logic. 

[jianli, 2015/11/06 00:04:40]

Yes, we only want to offer "Show all saved pages" button in the network offline
scenario which is probably the only case that the user cannot do more than
browsing the previously snapshot of certain pages.

+    base::DictionaryValue* show_saved_pages_button = new base::DictionaryValue;
+    show_saved_pages_button->SetString(
+        "msg", l10n_util::GetStringUTF16(
+            IDS_ERRORPAGES_BUTTON_SHOW_SAVED_PAGES));
+    show_saved_pages_button->SetString(
+        "title",
+        l10n_util::GetStringUTF16(IDS_ERRORPAGES_BUTTON_SHOW_SAVED_PAGES_HELP));
+    error_strings->Set("showSavedPagesButton", show_saved_pages_button);
+  }
+#endif
+
 #if defined(OS_CHROMEOS)
   // ChromeOS has its own diagnostics extension, which doesn't rely on a
   // browser-initiated dialog.
   can_show_network_diagnostics_dialog = true;
 #endif
   if (can_show_network_diagnostics_dialog && failed_url.is_valid() &&
       failed_url.SchemeIsHTTPOrHTTPS()) {
     error_strings->SetString(
         "diagnose", l10n_util::GetStringUTF16(IDS_ERRORPAGES_BUTTON_DIAGNOSE));
   }
@@ skipping 133 matching lines @@
     return l10n_util::GetStringUTF16(IDS_ERRORPAGES_DETAILS_UNKNOWN);
 }
 
 bool LocalizedError::HasStrings(const std::string& error_domain,
                                 int error_code) {
   // Whether or not the there are strings for an error does not depend on
   // whether or not the page was be generated by a POST, so just claim it was
   // not.
   return LookupErrorMap(error_domain, error_code, /*is_post=*/false) != NULL;
 }