Drives the two-phase install to completion. Both the Extensions view and the install-plugin deep link go through here, so either path shows the same dialogs and registers the same way.
install-plugin
true when the plugin was installed, false when the user cancelled either dialog.
Drives the two-phase install to completion. Both the Extensions view and the
install-plugindeep link go through here, so either path shows the same dialogs and registers the same way.