[cc] turn up low-res scale to 0.25.

[cc] turn up low-res scale to 0.25.

This increases the resolution at which "low-res" tiles are rasterized.
The goal is to improve the appearance of flings without reducing
performance. A separate patch will contain a SkDrawFilter to allow
reducing the quality at which "low-res" tiles are rasterized, and
we can determine independently when to activate that filter.

BUG=175976
TBR=nduca
CC=skyostil

[nduca, 2013-02-15 20:45:20]

-> brianderson for decision

[brianderson, 2013-02-15 23:50:42]

As discussed in email, we will hold off on this until we can make it faster for
slower devices.

Whether it's a low-quality mode or some kind of adaptive switching between 1/4
and 1/8 is TBD.

[Tom Hudson, 2013-02-19 11:48:44]

If we've got tablets going at 512x instead of 256x tiles, could we also use the
same tablet-detection logic to have the tablets scale at .25 instead of .125?