Remove dependency on ui::ScaleFactor from ui/gfx

ui/gfx/image/image_mac.mm

Index: ui/gfx/image/image_mac.mm
diff --git a/ui/gfx/image/image_mac.mm b/ui/gfx/image/image_mac.mm
index d03b48e0f4b72b67089a18b63691160f57fb32c2..15a56108342ac754d07fe4fdf758601c21c70712 100644
--- a/ui/gfx/image/image_mac.mm
+++ b/ui/gfx/image/image_mac.mm
@@ -65,7 +65,7 @@ NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps,
         [[NSBitmapImageRep alloc] initWithData:ns_data]);
     if (!ns_image_rep) {
       LOG(ERROR) << "Unable to decode PNG at "
-                 << ui::GetScaleFactorScale(image_png_reps[i].scale_factor)
+                 << image_png_reps[i].scale
                  << ".";
       return GetErrorNSImage();
     }
@@ -88,7 +88,7 @@ NSImage* NSImageFromPNG(const std::vector<gfx::ImagePNGRep>& image_png_reps,
     }
 
     if (!image.get()) {
-      float scale = ui::GetScaleFactorScale(image_png_reps[i].scale_factor);
+      float scale = image_png_reps[i].scale;
       NSSize image_size = NSMakeSize([ns_image_rep pixelsWide] / scale,
                                      [ns_image_rep pixelsHigh] / scale);
       image.reset([[NSImage alloc] initWithSize:image_size]);