Make JavaScript dialogs auto-dismiss on tab switch.

chrome/browser/ui/javascript_dialogs/javascript_dialog_tab_helper.h

 // Copyright 2016 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_JAVASCRIPT_DIALOGS_JAVASCRIPT_DIALOG_TAB_HELPER_H_
 #define CHROME_BROWSER_UI_JAVASCRIPT_DIALOGS_JAVASCRIPT_DIALOG_TAB_HELPER_H_
 
+#include <memory>
+
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "chrome/browser/ui/browser_list_observer.h"
 #include "content/public/browser/javascript_dialog_manager.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
+class JavaScriptDialogViews;
+
 class JavaScriptDialogTabHelper

[Peter Kasting, 2016/10/17 20:16:05]

Nit: While here: Would be nice to have an overview comment about the purpose of
this class.

[Avi (use Gerrit), 2016/10/18 02:46:41]

Done.

     : public content::WebContentsObserver,
+      public chrome::BrowserListObserver,
       public content::JavaScriptDialogManager,
       public content::WebContentsUserData<JavaScriptDialogTabHelper> {
  public:
   explicit JavaScriptDialogTabHelper(content::WebContents* web_contents);
   ~JavaScriptDialogTabHelper() override;
 
   // JavaScriptDialogManager:
   void RunJavaScriptDialog(content::WebContents* web_contents,
                            const GURL& origin_url,
                            content::JavaScriptMessageType message_type,
                            const base::string16& message_text,
                            const base::string16& default_prompt_text,
                            const DialogClosedCallback& callback,
                            bool* did_suppress_message) override;
   void RunBeforeUnloadDialog(content::WebContents* web_contents,
                              bool is_reload,
                              const DialogClosedCallback& callback) override;
   bool HandleJavaScriptDialog(content::WebContents* web_contents,
                               bool accept,
                               const base::string16* prompt_override) override;
   void CancelDialogs(content::WebContents* web_contents,
                      bool suppress_callbacks,
                      bool reset_state) override;
-  void WebContentsDestroyed() override;
+
+  // WebContentsObserver:

[Peter Kasting, 2016/10/17 20:16:04]

Nit: Keep blocks of overrides and superclass list in same order

[Avi (use Gerrit), 2016/10/18 02:46:41]

Done.

+  void WasHidden() override;
+
+  // BrowserListObserver:
+  void OnBrowserSetLastActive(Browser* browser) override;
 
  private:
   friend class content::WebContentsUserData<JavaScriptDialogTabHelper>;
 
+  void CloseDialog(bool suppress_callback,
+                   bool success,
+                   const base::string16& user_input);
+
+  // The dialog being displayed on the observed WebContents.
+  base::WeakPtr<JavaScriptDialogViews> dialog_;
+
+  // The callback provided for when the dialog is closed. Usually the dialog
+  // itself calls it, but this class will do in some cases.

[Peter Kasting, 2016/10/17 20:16:05]

Nit: "will do it" or "will do so".  Would be nice to refer to some comment
elsewhere that would make it clear what these kinds of cases might be (e.g. the
class overview comment mentioned above?).

[Avi (use Gerrit), 2016/10/18 02:46:41]

Done.

+  content::JavaScriptDialogManager::DialogClosedCallback dialog_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(JavaScriptDialogTabHelper);
 };
 
 #endif  // CHROME_BROWSER_UI_JAVASCRIPT_DIALOGS_JAVASCRIPT_DIALOG_TAB_HELPER_H_