Replace OnPageTranslate Obsever by a responder of delegate.

chrome/browser/ui/android/infobars/translate_compact_infobar.h

 // Copyright 2017 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.
 
 #ifndef CHROME_BROWSER_UI_ANDROID_INFOBARS_TRANSLATE_COMPACT_INFOBAR_H_
 #define CHROME_BROWSER_UI_ANDROID_INFOBARS_TRANSLATE_COMPACT_INFOBAR_H_
 
 #include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
 #include "chrome/browser/translate/chrome_translate_client.h"
 #include "chrome/browser/ui/android/infobars/infobar_android.h"
-#include "components/translate/content/browser/content_translate_driver.h"
+#include "components/translate/core/browser/translate_infobar_delegate.h"
+#include "components/translate/core/browser/translate_step.h"
+#include "components/translate/core/common/translate_errors.h"
 
 namespace translate {
 class TranslateInfoBarDelegate;
 }
 
 class TranslateCompactInfoBar
     : public InfoBarAndroid,
-      public translate::ContentTranslateDriver::Observer {
+      public translate::TranslateInfoBarDelegate::Responder {
  public:
   explicit TranslateCompactInfoBar(
       std::unique_ptr<translate::TranslateInfoBarDelegate> delegate);
   ~TranslateCompactInfoBar() override;
 
   // JNI method specific to string settings in translate.
   void ApplyStringTranslateOption(
       JNIEnv* env,
       const base::android::JavaParamRef<jobject>& obj,
       int option,
       const base::android::JavaParamRef<jstring>& value);
 
   // JNI method specific to boolean settings in translate.
   void ApplyBoolTranslateOption(JNIEnv* env,
                                 const base::android::JavaParamRef<jobject>& obj,
                                 int option,
                                 jboolean value);
 
   // Check whether we should automatically trigger "Always Translate".
   bool ShouldAutoAlwaysTranslate();
 
   // Check whether we should automatically trigger "Never Translate Language".
   jboolean ShouldAutoNeverTranslate(
       JNIEnv* env,
       const base::android::JavaParamRef<jobject>& obj);
 
-  // ContentTranslateDriver::Observer implementation.
-  void OnPageTranslated(const std::string& original_lang,

[groby-ooo-7-16, 2017/05/20 21:30:39]

Who is notifying the ContentTranslateDriver now?

[Leo, 2017/05/21 04:15:20]

This method is used when ContentTranslateDriver finished translation and notify
the observer to update its state.

With or without a observer, translate manager will be called when page
translation finished. 
https://cs.chromium.org/chromium/src/components/translate/content/browser/con...

So the following things will always happen with or without observer.

ContentTranslateDriver:OnPageTranslated  >> 
TranslateManager::PageTranslated >>
TranslateClient::ShowTranslateUI >>
TranslateInfoBarDelegate::Create

So I remove this observer stuff in compact infobar but respond the
onPageTranslated event inside TranslateInfoBarDelegate

-                        const std::string& translated_lang,
-                        translate::TranslateErrors::Type error_type) override;
+  // TranslateInfoBarDelegate::Responder implementation.
+  void ActionOnStep(translate::TranslateStep step,
+                    translate::TranslateErrors::Type error_type) override;
+  bool Declined() override;
 
  private:
   // InfoBarAndroid:
   base::android::ScopedJavaLocalRef<jobject> CreateRenderInfoBar(
       JNIEnv* env) override;
   void ProcessButton(int action) override;
   void SetJavaInfoBar(
       const base::android::JavaRef<jobject>& java_info_bar) override;
 
   translate::TranslateInfoBarDelegate* GetDelegate();
-  translate::ContentTranslateDriver* translate_driver_;
+
+  // Bits for trace user actions.
+  unsigned int action_flags_;

[groby-ooo-7-16, 2017/05/20 21:30:39]

This should be of type ActionFlag if you use the enum.

As a _personal_ preference, I'd prefer a bitfield. But ultimately, either is
fine.
 struct {
    bool did_translate_ : 1;
    bool did_revert_ : 1;
    ...
  } flags;

[napper, 2017/05/21 23:24:16]

I think the int type is correct here, since the enum specifies bit flags, not
values. The following would not be correct for an enum but is correct for an int
type:

action_flags_ = FLAG_TRANSLATE | FLAG_NEVER_LANGUAGE;

But I agree, a bitfield might be cleaner.

[Leo, 2017/05/22 09:08:10]

After a little discuss offline with Jon. Seems the initialization of the struct
is not as simple as int and it may introduce other considerations. How about let
me keep this way and refactor it in another CL.

[groby-ooo-7-16, 2017/05/22 14:34:11]

You are of course right about the int - sorry about the confusion.

[groby-ooo-7-16, 2017/05/22 14:34:11]

No need to refactor if it introduces many other issues. (As I said, it's a
personal preference of mine - but just because I like something a bit better
aesthethically doesn't mean you should have a lot of extra work :)

+
+  // User action flags to record what the user has done in each session.
+  enum ActionFlag {
+    FLAG_NONE = 0,
+    FLAG_TRANSLATE = 1 << 0,
+    FLAG_REVERT = 1 << 1,
+    FLAG_ALWAYS_TRANSLATE = 1 << 2,
+    FLAG_NEVER_LANGUAGE = 1 << 3,
+    FLAG_NEVER_SITE = 1 << 4,
+  };
 
   // If number of consecutive translations is equal to this number, infobar will
   // automatically trigger "Always Translate".
   const int kAcceptCountThreshold = 5;
   // If number of consecutive denied is equal to this number, infobar will
   // automatically trigger "Never Translate Language".
   const int kDeniedCountThreshold = 7;
 
   DISALLOW_COPY_AND_ASSIGN(TranslateCompactInfoBar);
 };
 
 // Registers the native methods through JNI.
 bool RegisterTranslateCompactInfoBar(JNIEnv* env);
 
 #endif  // CHROME_BROWSER_UI_ANDROID_INFOBARS_TRANSLATE_COMPACT_INFOBAR_H_