Reland cmaa, gpu: use R8 image texture when GL_NV_image_formats is available.

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 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.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 17585 matching lines @@
     glApplyFramebufferAttachmentCMAAINTEL();
   } else {
     // Defer initializing the CopyTextureCHROMIUMResourceManager until it is
     // needed because it takes ??s of milliseconds to initialize.
     if (!apply_framebuffer_attachment_cmaa_intel_.get()) {
       LOCAL_COPY_REAL_GL_ERRORS_TO_WRAPPER(
           "glApplyFramebufferAttachmentCMAAINTEL");
       apply_framebuffer_attachment_cmaa_intel_.reset(
           new ApplyFramebufferAttachmentCMAAINTELResourceManager());
       apply_framebuffer_attachment_cmaa_intel_->Initialize(this);
-      RestoreCurrentFramebufferBindings();
       if (LOCAL_PEEK_GL_ERROR("glApplyFramebufferAttachmentCMAAINTEL") !=
           GL_NO_ERROR)
         return;
     }
     static const char kFunctionName[] =
         "glApplyScreenSpaceAntialiasingCHROMIUM";
     if (!InitializeCopyTextureCHROMIUM(kFunctionName))
       return;
     for (uint32_t i = 0; i < group_->max_draw_buffers(); ++i) {
       const Framebuffer::Attachment* attachment =
@@ skipping 1877 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu