No, the distinction of device pixels vs. CSS pixels predates the first "Retina" iPhone. The distinction existed in all browsers supporting full page zoom, including the Safari on the first iPhone, and in Opera for years before that.
"Retina" is just a marketing term for "pixels so small your eye can't distinguish them at a normal distance anymore".
The distinction is also in CSS specs[0] since version 2.1: “The reference pixel is the visual angle of one pixel on a device with a pixel density of 96dpi and a distance from the reader of an arm's length. <…> 1px thus corresponds to about 0.26 mm (1/96 inch).”
"Retina" is just a marketing term for "pixels so small your eye can't distinguish them at a normal distance anymore".