No. It doesn't changed the emulator. What it did is that IE will act on behalf of other browser. Some websites react differently in each browser, IE, Chrome, Mozilla, etc. and they did this using user agent. If you inject user agent of Chrome in IE, website will throw a respond intended for Chrome browser, even though you are using IE.
The line may work and sometimes not. But works most of the time. The bottom line is we are going to find a way for the "Add to Cart" to work.