display error message for empty distilled content

components/dom_distiller/core/viewer.cc

 // Copyright 2014 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 "components/dom_distiller/core/viewer.h"
 
 #include <string>
 #include <vector>
 
 #include "base/json/json_writer.h"
@@ skipping 71 matching lines @@
 // Maps fontFamilies to CSS fontFamily classes.
 const std::string GetFontCssClass(DistilledPagePrefs::FontFamily font_family) {
   if (font_family == DistilledPagePrefs::SERIF) {
     return kSerifCssClass;
   } else if (font_family == DistilledPagePrefs::MONOSPACE) {
     return kMonospaceCssClass;
   }
   return kSansSerifCssClass;
 }
 
+void EnsureNonEmptyTitleAndContent(std::string* title, std::string* content) {
+  if (title->empty())
+    *title = l10n_util::GetStringUTF8(IDS_DOM_DISTILLER_VIEWER_NO_DATA_TITLE);
+  if (content->empty()) {
+    *content = l10n_util::GetStringUTF8(
+        IDS_DOM_DISTILLER_VIEWER_NO_DATA_CONTENT);
+  }
+}
+
 std::string ReplaceHtmlTemplateValues(
     const std::string& title,
     const std::string& content,
     const std::string& loading_indicator_class,
     const std::string& original_url,
     const DistilledPagePrefs::Theme theme,
     const DistilledPagePrefs::FontFamily font_family) {
   base::StringPiece html_template =
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_DOM_DISTILLER_VIEWER_HTML);
@@ skipping 37 matching lines @@
 
 const std::string GetUnsafePartialArticleHtml(
     const DistilledPageProto* page_proto,
     const DistilledPagePrefs::Theme theme,
     const DistilledPagePrefs::FontFamily font_family) {
   DCHECK(page_proto);
   std::string title = net::EscapeForHTML(page_proto->title());
   std::ostringstream unsafe_output_stream;
   unsafe_output_stream << page_proto->html();
   std::string unsafe_article_html = unsafe_output_stream.str();
+  EnsureNonEmptyTitleAndContent(&title, &unsafe_article_html);
   std::string original_url = page_proto->url();
   return ReplaceHtmlTemplateValues(
       title, unsafe_article_html, "visible", original_url, theme, font_family);
 }
 
 const std::string GetUnsafeArticleHtml(
     const DistilledArticleProto* article_proto,
     const DistilledPagePrefs::Theme theme,
     const DistilledPagePrefs::FontFamily font_family) {
   DCHECK(article_proto);
   std::string title;
   std::string unsafe_article_html;
   if (article_proto->has_title() && article_proto->pages_size() > 0 &&
       article_proto->pages(0).has_html()) {
     title = net::EscapeForHTML(article_proto->title());
     std::ostringstream unsafe_output_stream;
     for (int page_num = 0; page_num < article_proto->pages_size(); ++page_num) {
       unsafe_output_stream << article_proto->pages(page_num).html();
     }
     unsafe_article_html = unsafe_output_stream.str();
-  } else {
-    title = l10n_util::GetStringUTF8(IDS_DOM_DISTILLER_VIEWER_NO_DATA_TITLE);
-    unsafe_article_html =
-        l10n_util::GetStringUTF8(IDS_DOM_DISTILLER_VIEWER_NO_DATA_CONTENT);
   }
 
+  EnsureNonEmptyTitleAndContent(&title, &unsafe_article_html);
+
   std::string original_url;
   if (article_proto->pages_size() > 0 && article_proto->pages(0).has_url()) {
     original_url = article_proto->pages(0).url();
   }
 
   return ReplaceHtmlTemplateValues(
       title, unsafe_article_html, "hidden", original_url, theme, font_family);
 }
 
 const std::string GetErrorPageHtml(
@@ skipping 60 matching lines @@
 }
 
 const std::string GetDistilledPageFontFamilyJs(
     DistilledPagePrefs::FontFamily font_family) {
   return "useFontFamily('" + GetJsFontFamily(font_family) + "');";
 }
 
 }  // namespace viewer
 
 }  // namespace dom_distiller