Fix an issue with FireFox where it blurs when copying from a smaller to a

Fix an issue with FireFox where it blurs when copying from a smaller to a
larger canvas. Work around that by drawing a rect for each pixel.

Also, add a drop shadow to the hex display so you can see it on a dark background color.

BUG=skia:

Committed: http://code.google.com/p/skia/source/detail?r=14575

[mtklein, 2014-05-05 18:36:36]

lgtm

[jcgregorio, 2014-05-05 18:36:46]

The CQ bit was checked by jcgregorio@google.com

[commit-bot: I haz the power, 2014-05-05 18:37:05]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/jcgregorio@google.com/261303002/1

[commit-bot: I haz the power, 2014-05-05 18:43:18]

Change committed as 14575