Added an abstract invalidate method to rx::RenderTarget.

TRAC #23133

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

git-svn-id: https://angleproject.googlecode.com/svn/branches/es3proto@2334 736b8ea6-26fd-11df-bfd4-992fa37f6226
5 files changed