Turn on auto-dismissing dialogs for trunk builds.

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/callback_forward.h"
@@ skipping 19 matching lines @@
 class JavaScriptDialogTabHelper
     : public content::JavaScriptDialogManager,
       public content::WebContentsObserver,
       public chrome::BrowserListObserver,
       public content::WebContentsUserData<JavaScriptDialogTabHelper> {
  public:
   explicit JavaScriptDialogTabHelper(content::WebContents* web_contents);
   ~JavaScriptDialogTabHelper() override;
 
   void SetDialogShownCallbackForTesting(base::Closure callback);
+  bool IsShowingDialogForTesting();

[Devlin, 2017/05/01 17:12:22]

drive-by nit: bool IsShowingDialogForTesting() const;

[Avi (use Gerrit), 2017/05/01 18:55:23]

Done.

 
   // JavaScriptDialogManager:
   void RunJavaScriptDialog(content::WebContents* web_contents,
                            const GURL& origin_url,
                            content::JavaScriptDialogType dialog_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,
@@ skipping 45 matching lines @@
   // itself calls it, but in the cases where the dialog is closed not by the
   // user's input but by a call to |CloseDialog|, this class will call it.
   content::JavaScriptDialogManager::DialogClosedCallback dialog_callback_;
 
   base::Closure dialog_shown_;
 
   DISALLOW_COPY_AND_ASSIGN(JavaScriptDialogTabHelper);
 };
 
 #endif  // CHROME_BROWSER_UI_JAVASCRIPT_DIALOGS_JAVASCRIPT_DIALOG_TAB_HELPER_H_