Have tree-less tab bar replacement view

I'd just like to use TF as a tab bar replacement. I imagine that TF could have an option to live as a sort of replacement tab bar for Google's awful tab bar. I keep it open in a column to the left of a single browser window. The top-level tree view takes up valuable pixels in a vertical bar to the left of the tab. I think TF might just only show the tabs in the active window, changing them when another gets activated. True, it might not always be to the left of the newly activated window, but I can resize TF and the windows so that TF is always in a little vertical bar to the left of my active window.

No file, test, or entry point is named. Start by locating the tree and tab-bar views and the code that tracks the active Chrome window; determine how an option could show only that window's tabs and update on activation. Done means the tree-less replacement view remains synchronized with the active window.

Written by the indexing model from the issue text.