Expose history to the content feed

[fernandojsg]

As proposed for the bookmarks (#442), but for the history.
The content feed should be able to remove content from the list. It doesn't necessarily need to be a two-ways api as we could just blacklist some urls when deleting them from the content feed on the localstorage.

[keianhzo]

GV is getting a History API https://bugzilla.mozilla.org/show_bug.cgi?id=1494713. When this is closed we should open a new issue to track that and update.

[philip-lamb]

https://bugzilla.mozilla.org/show_bug.cgi?id=1494713 is done.

[cvan]

See discussion from the original PR from prior to the implementation of the GeckoView History API: #457 (comment)

This bug needs attention re: Privacy, Security, and UX. We may be able to close this. But even if we conclude that the Content Feed should feature History (instead of accessible from about:history, à la about:bookmarks / the Bookmarks button in the Tray), the work needs to be done in #614 to first use the android-components code.

[jvonitter]

tracking this in #759