21efb6827c
PngCrunching now has a slightly better heuristic of choosing to encode an image as a palette or RGB. For small images, RGB compresses much better than a palette. The original PNG is used as-is (minus some optional chunks being stripped) if the resulting crunched PNG is larger than the original. 9-patch handling is abstracted away from PNGs, paving the way for other 9-patches, like WebP. TODO: handle PNGs with 9-patch chunks already present, which should just be passed through. This will allow for 3rd party tools to generate 9-patches. TODO: implement cheap transparency: when one color is used to represent transparent, and all other colors are opaque. Bug:30053276 Change-Id: I5167f53b91d1efa462d9f03d6b9108d9b541c0c1