Move vertex layout from GeometrySrcState to GrDrawState.

Also adds AutoStateRestore member to AutoGeometryPush to push DrawState as well
as GeometrySrcState. And removed vertex layout as an argument to a number of 
functions -- they will get vertex layout info from the current DrawState.

Review URL: https://codereview.appspot.com/7286047


git-svn-id: http://skia.googlecode.com/svn/trunk@7600 2bbb7eff-a529-9590-31e7-b0007b416f81
15 files changed