use browser.devicePixelRatio instead of directly calling window.devic…

…ePixelRatio (#9063)

h/t @pakastin

src/ui/map.js

@@ -1967,7 +1967,7 @@ class Map extends Camera {
     }
 
     _resizeCanvas(width: number, height: number) {
-        const pixelRatio = window.devicePixelRatio || 1;
+        const pixelRatio = browser.devicePixelRatio || 1;
 
         // Request the required canvas size taking the pixelratio into account.
         this._canvas.width = pixelRatio * width;