Fix two bugs when deciding to tile. Large images were always tiling.

usedTileBytes was actually usedTileTexels, so we underestimated how much
of the image we were using by a factor of 4.

Then, to determine if we were using more than 50% of the image, we wrote:
usedTileBytes < 2 * bmpSize;

That meant we were off by another factor of 4.

BUG=skia:

Change-Id: Iba2acc75c5e7603543f05e4473b73f76a2937d7a
Reviewed-on: https://skia-review.googlesource.com/8063
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
1 file changed