Check |errorCode| of translate.js and notify to Browser

components/translate/content/renderer/translate_helper.cc

Index: components/translate/content/renderer/translate_helper.cc
diff --git a/components/translate/content/renderer/translate_helper.cc b/components/translate/content/renderer/translate_helper.cc
index f1b8ce439604062e46d72094d4f05731725861dc..d66f1bc4f2d9b1b2d186ad5de6cc0b09959eb5d9 100644
--- a/components/translate/content/renderer/translate_helper.cc
+++ b/components/translate/content/renderer/translate_helper.cc
@@ -60,6 +60,13 @@ const char kAutoDetectionLanguage[] = "auto";
 // Isolated world sets following content-security-policy.
 const char kContentSecurityPolicy[] = "script-src 'self' 'unsafe-eval'";
 
+// Converts the error value returned by 'cr.googleTranslate.errorCode' to
+// TranslateErrors::Type.
+translate::TranslateErrors::Type ErrorCodeToTranslateErrorType(
+    int64_t error_code) {
+  return static_cast<translate::TranslateErrors::Type>(error_code);
+}
+
 }  // namespace
 
 namespace translate {
@@ -252,6 +259,25 @@ double TranslateHelper::ExecuteScriptAndGetDoubleResult(
   return results[0]->NumberValue();
 }
 
+int64_t TranslateHelper::ExecuteScriptAndGetIntegerResult(
+    const std::string& script,
+    int64_t fallback) {
+  WebLocalFrame* main_frame = render_frame()->GetWebFrame();
+  if (!main_frame)
+    return fallback;
+
+  v8::HandleScope handle_scope(v8::Isolate::GetCurrent());
+  WebVector<v8::Local<v8::Value>> results;
+  WebScriptSource source = WebScriptSource(WebString::FromASCII(script));
+  main_frame->ExecuteScriptInIsolatedWorld(world_id_, &source, 1, &results);
+  if (results.size() != 1 || results[0].IsEmpty() || !results[0]->IsNumber()) {
+    NOTREACHED();
+    return fallback;
+  }
+
+  return results[0]->IntegerValue();
+}
+
 // mojom::Page implementations.
 void TranslateHelper::Translate(const std::string& translate_script,
                                 const std::string& source_lang,
@@ -325,8 +351,10 @@ void TranslateHelper::RevertTranslation() {
 void TranslateHelper::CheckTranslateStatus() {
   // First check if there was an error.
   if (HasTranslationFailed()) {
-    // TODO(toyoshim): Check |errorCode| of translate.js and notify it here.
-    NotifyBrowserTranslationFailed(TranslateErrors::TRANSLATION_ERROR);
+    int64_t error_code = ExecuteScriptAndGetIntegerResult(
+        "cr.googleTranslate.errorCode",
+        static_cast<int>(TranslateErrors::TRANSLATION_ERROR));
+    NotifyBrowserTranslationFailed(ErrorCodeToTranslateErrorType(error_code));

[Takashi Toyoshima, 2017/06/14 04:00:02]

Probably it's consistent to use static_cast<TranslateErrors> directly here.

Because you already use static_cast<int> for converting TranslateErros to
errorCode. There is no reason to do the reversed conversion in a different way.

[Gaja, 2017/06/14 06:53:11]

Acknowledged. Ok, this seems better.

     return;  // There was an error.
   }