Expose EXT_discard_framebuffer

mojo/gpu/mojo_gles2_impl_autogen.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file is auto-generated from
 // gpu/command_buffer/build_gles2_cmd_buffer.py
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 1524 matching lines @@
 }
 void MojoGLES2Impl::WaitAsyncTexImage2DCHROMIUM(GLenum target) {
   NOTREACHED() << "Unimplemented WaitAsyncTexImage2DCHROMIUM.";
 }
 void MojoGLES2Impl::WaitAllAsyncTexImage2DCHROMIUM() {
   NOTREACHED() << "Unimplemented 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.";
 }
 GLuint MojoGLES2Impl::InsertSyncPointCHROMIUM() {
   MojoGLES2MakeCurrent(context_);
   return glInsertSyncPointCHROMIUM();
 }
 void MojoGLES2Impl::WaitSyncPointCHROMIUM(GLuint sync_point) {
   MojoGLES2MakeCurrent(context_);
@@ skipping 26 matching lines @@
 }
 void MojoGLES2Impl::MatrixLoadIdentityCHROMIUM(GLenum matrixMode) {
   NOTREACHED() << "Unimplemented MatrixLoadIdentityCHROMIUM.";
 }
 void MojoGLES2Impl::BlendBarrierKHR() {
   MojoGLES2MakeCurrent(context_);
   glBlendBarrierKHR();
 }
 
 }  // namespace mojo