Resend viewport on render target change. The viewport is reset upon SetRenderTarget, so make sure to do SetViewport again. BUG= TEST= Review URL: http://codereview.appspot.com/5334048 git-svn-id: https://angleproject.googlecode.com/svn/trunk@812 736b8ea6-26fd-11df-bfd4-992fa37f6226