Navigation initiated by history.back() should overwrite child frame reload, which was started eralier and did not finish yet. History state at the end should reflect the back() call.
============== Back Forward List ==============
http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html
about:blank (in frame "<!--framePath //<!--frame0-->-->")
curr-> http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html?one
about:blank (in frame "<!--framePath //<!--frame0-->-->")
http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html?one?two
about:blank (in frame "<!--framePath //<!--frame0-->-->")
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