Reassigning to myself since this also blocks getting good stats on whether navigations come from user input.

The callstack to do a back navigation from the browser back button looks like this (similar stack for keypress):

content::NavigationControllerImpl::NavigateToExistingPendingEntry()
content::NavigationControllerImpl::GotToIndex()
content::NavigationControllerImpl::GoBack()
chrome::GoBack()
chrome::BrowserCommandController::ExecuteCommandWithDisposition()
views::Button::OnMouseReleased()

The input timestamp is known in OnMouseReleased(). But ExecuteCommandWithDisposition, GoBack, and NavigationController::GoBack() are all public methods with no arguments to pass an input timestamp through.

This is different from the omnibox in  bug 750639 , where I was able to cache the timestamp of the input and pass it in as an argument in NavigationControllerImpl::LoadURLWithParams().

Anyone have good ideas on how to plumb a timestamp through?

+dgozman, you've helped me with plumbing data through navigation before, do you have ideas here, or thoughts on who would be good to ask? I'd want to be able to do something really similar on toolbar button click, keypress, and context menu for back, forward, reload, and home.

+nasko, who is more familiar with NavigationController.