Enable subframe FrameNavigationEntries by default.
This is a major change to the navigation logic in Chrome, making
the browser process responsible for selecting subframes to
navigate. Each NavigationEntry now has a tree of
FrameNavigationEntries representing each frame in the page, and
these frame entries track per-frame PageState.
HistoryController in content/renderer is no longer used, since
equivalent code in NavigationController in content/browser now
determines which frames to navigate.
This CL is designed to be easy to revert if regressions are
found, though the new path has been in use on 50% of Canary and
Dev channels for a while.
BUG=236848
TEST=Existing tests pass.
Review-Url: https://codereview.chromium.org/2205053002
Cr-Commit-Position: refs/heads/master@{#410150}
2 files changed
