Changed the rectangle arguments of Renderer11::blitRect from pointers to const references since they are never null or modified.

TRAC #22416

Signed-off-by: Jamie Madill
Signed-off-by: Shannon Woods
Author: Geoff Lang

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1869 736b8ea6-26fd-11df-bfd4-992fa37f6226