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

components/translate/content/renderer/translate_helper.h

Index: components/translate/content/renderer/translate_helper.h
diff --git a/components/translate/content/renderer/translate_helper.h b/components/translate/content/renderer/translate_helper.h
index 622e7183fc6e8c11a6ab71b4fd263b0f8523f749..5b8a0735c7809e60232971e0f1521e36c71b38bd 100644
--- a/components/translate/content/renderer/translate_helper.h
+++ b/components/translate/content/renderer/translate_helper.h
@@ -64,6 +64,9 @@ class TranslateHelper : public content::RenderFrameObserver,
   // translation.
   virtual bool HasTranslationFailed();
 
+  // Returns the error code generated in translate library.
+  virtual int64_t GetErrorCode();

[napper, 2017/06/16 12:41:51]

Can this method (and the one below) be const?

[Takashi Toyoshima, 2017/06/16 16:14:17]

IMHO, the method causes a side effect should not be const even though it does
not change member variables.
Especially for the method below, it executes arbitrary JavaScript code on v8.
That should not be const.

+
   // Starts the translation by calling the translate library.  This method
   // should only be called when the translate script has been injected in the
   // page.  Returns false if the call failed immediately.
@@ -98,6 +101,12 @@ class TranslateHelper : public content::RenderFrameObserver,
   // run successfully. Otherwise, returns 0.0.
   virtual double ExecuteScriptAndGetDoubleResult(const std::string& script);
 
+  // Executes the JavaScript code in |script| in the main frame of RenderView.
+  // and returns the integer value returned by the script evaluation if the
+  // script was run successfully. Otherwise, returns |fallback| value.
+  virtual int64_t ExecuteScriptAndGetIntegerResult(const std::string& script,
+                                                   int64_t fallback);
+
  private:
   // Converts language code to the one used in server supporting list.
   static void ConvertLanguageCodeSynonym(std::string* code);