Bug 1104270 - fix eager font and image parsing

Btw, the naming scheme changes when applied to byte arrays vs numbers. When referring to numbers, ARGB means that the A component is from bit 32 to 25. When referring to byte buffers, little endian order is assumed, so:

```
var pARGB = new Int32Array(...);
var pBGRA = pARGB[0];
```

I'm open to changing this scheme if you think it's confusing.