Move the device capability method to SkDevice.

These are not the capabilities of the factory, but of the device.  Additionally, it is more often needed when you have a device then when you have a factory, which caused creating of a new factory.

Review URL: http://codereview.appspot.com/2720041

git-svn-id: http://skia.googlecode.com/svn/trunk@618 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed