Notify the renderer if a history navigation has no subframe items.
In this case, the renderer does not need to consult the browser
process if subframes are created during the navigation. Since there
are no history items for it, the renderer can just load the default
URL.
BUG=638088, 639842
TEST=Restore chrome://settings after disabling MD settings mode.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
Review-Url: https://codereview.chromium.org/2316003002
Cr-Commit-Position: refs/heads/master@{#420486}
10 files changed
