Add perspective support to SkMatrix44 initializers.

I noticed SkMatrix <-> SkMatrix44 conversions were dropping the
perspective values on the floor.  As we use SkMatrix44 heavily in
Chromium, I'm concerned this missing code will cause a bug eventually.
It should be correct to simply use the bottom row of the 4x4 matrix
excluding the third column.

BUG=
R=reed@google.com

Author: aelias@chromium.org

Review URL: https://codereview.chromium.org/25484006

git-svn-id: http://skia.googlecode.com/svn/trunk/src@11622 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed