I suspect the toolbar is there to clearly identify the origin URL. As you can see, safari gives you no hint that this page is not actually google: https://imgur.com/a/2BtMX
As for the X button, I suppose google wishes people to use google search result like a news reader. I agree that it is redundant with the back button but the interaction does seem faster (I suspect that the page is actually loaded in an iframe on top of the results page)
As for the X button, I suppose google wishes people to use google search result like a news reader. I agree that it is redundant with the back button but the interaction does seem faster (I suspect that the page is actually loaded in an iframe on top of the results page)