Expose EXT_discard_framebuffer

mojo/gpu/mojo_gles2_impl_autogen.cc

Index: mojo/gpu/mojo_gles2_impl_autogen.cc
diff --git a/mojo/gpu/mojo_gles2_impl_autogen.cc b/mojo/gpu/mojo_gles2_impl_autogen.cc
index 7842a3ae1c040bc7e71fbd2bf9bba0c2bcbf137f..2fb812ee6f5af9b3fce6248554ddd7c58f24a394 100644
--- a/mojo/gpu/mojo_gles2_impl_autogen.cc
+++ b/mojo/gpu/mojo_gles2_impl_autogen.cc
@@ -1542,7 +1542,8 @@ void MojoGLES2Impl::WaitAllAsyncTexImage2DCHROMIUM() {
 void MojoGLES2Impl::DiscardFramebufferEXT(GLenum target,
                                           GLsizei count,
                                           const GLenum* attachments) {
-  NOTREACHED() << "Unimplemented DiscardFramebufferEXT.";
+  MojoGLES2MakeCurrent(context_);
+  glDiscardFramebufferEXT(target, count, attachments);
 }
 void MojoGLES2Impl::LoseContextCHROMIUM(GLenum current, GLenum other) {
   NOTREACHED() << "Unimplemented LoseContextCHROMIUM.";