Render: set minimum render size to 1x1 instead of 2x2. As far as I can tell this
works ok, and it's useful for debugging.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@53811 954f8c5b-7b00-dc11-b283-0030488c597c
Fix #33741,#33856: multi texture drawing problem with VBO's after a recent bugfix.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@53812 954f8c5b-7b00-dc11-b283-0030488c597c