Support to add a button to file browser. (Git Extension Support 1/2)

[tgeorgeux]

For the Git Extension, we're trying to integrate the experience with the existing file browser. The first order of business was to add a 'clone repo' button to the file browser. I was wondering what it would take to expose the API for the file browser so an extension could do something like this (Red outline is there to highlight the new feature, I'm not looking to add a bright red outline to the UI):

cc: @jaipreet-s , @weihwang

[jaipreet-s]

This is do-able in a fairly clean way today without having to resort to DOM manipulation

A plugin can request an IFileBrowserFactory, access the toolbar element, and add a ToolbarButton

let toolbar = factory.defaultBrowser.toolbar;
 toolbar.addItem('myButton', new ToolbarButton({...});

[ian-r-rose]

Thanks @jaipreet-s