Always restart the hung page timer after a beforeunload dialog.

content/browser/frame_host/render_frame_host_impl.h

Index: content/browser/frame_host/render_frame_host_impl.h
diff --git a/content/browser/frame_host/render_frame_host_impl.h b/content/browser/frame_host/render_frame_host_impl.h
index 103a23ed1515f094d3d18ebc38c7684a07a119ea..cb29e92a67631ac245fe54c4e90197c8bf7287c3 100644
--- a/content/browser/frame_host/render_frame_host_impl.h
+++ b/content/browser/frame_host/render_frame_host_impl.h
@@ -463,7 +463,8 @@ class CONTENT_EXPORT RenderFrameHostImpl
 
   // Notifies the RenderFrame that the JavaScript message that was shown was
   // closed by the user.
-  void JavaScriptDialogClosed(IPC::Message* reply_msg,
+  void JavaScriptDialogClosed(bool is_before_unload_dialog,

[Charlie Reis, 2017/02/27 18:41:41]

nit: I'd suggest putting this down near dialog_was_suppressed, since it's more
about the context in which the call was made than the primary arguments
(reply_msg, success, user_input).

[Avi (use Gerrit), 2017/02/27 19:28:49]

Done.

+                              IPC::Message* reply_msg,
                               bool success,
                               const base::string16& user_input,
                               bool dialog_was_suppressed);