Don't wait to close tabs waiting for JavaScript dialogs.

content/browser/renderer_host/render_view_host_delegate.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 222 matching lines @@
   // this page or not. If it has, this can be used to suppress things like the
   // link disambiguation dialog, which doesn't interact well with the virtual
   // keyboard.
   virtual void SetIsVirtualKeyboardRequested(bool requested) {}
   virtual bool IsVirtualKeyboardRequested();
 
   // Whether the user agent is overridden using the Chrome for Android "Request
   // Desktop Site" feature.
   virtual bool IsOverridingUserAgent();
 
+  virtual bool IsJavaScriptDialogShowing() const;
+
  protected:
   virtual ~RenderViewHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_