check network connectivity in onPageTranslated callback.

components/translate/core/browser/translate_manager.cc

Index: components/translate/core/browser/translate_manager.cc
diff --git a/components/translate/core/browser/translate_manager.cc b/components/translate/core/browser/translate_manager.cc
index a9970118034e3e73f40a23708807374f4f75ff40..b714d3f99ccc7bf05d26a9e39069b80a84d4665e 100644
--- a/components/translate/core/browser/translate_manager.cc
+++ b/components/translate/core/browser/translate_manager.cc
@@ -361,6 +361,13 @@ void TranslateManager::TranslatePage(const std::string& original_source_lang,
 
   const std::string& script_data = script->data();
   if (!script_data.empty()) {
+    if (net::NetworkChangeNotifier::IsOffline()) {
+      translate_client_->ShowTranslateUI(
+          translate::TRANSLATE_STEP_TRANSLATE_ERROR, source_lang, target_lang,
+          TranslateErrors::NETWORK, false);
+      return;
+    }
+
     DoTranslatePage(script_data, source_lang, target_lang);
     return;
   }