OutOfMemory with Images in WP8

When trying to load an RSS feed into a ListView, I kept hitting OOM exceptions on WP8. Digging deeper, the issue stems from the ImageRenderer not setting an appropriate DecodeImageHeight/DecodeImageWidth on the BitmapImage, so it takes up too much memory.

I worked around it with a custom renderer on Images, but something as basic as this should be the default. Basically, if RequestedHeight/RequestedWidth is specified on the image, it should set the decode values on the BitmapImage.