Enable asynchronous glReadPixels on Windows.

gpu/command_buffer/service/feature_info.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/feature_info.h"
 
 #include <set>
 
 #include "base/command_line.h"
 #include "base/macros.h"
@@ skipping 837 matching lines @@
   if (workarounds_.disable_egl_khr_fence_sync) {
     gfx::g_driver_egl.ext.b_EGL_KHR_fence_sync = false;
   }
 #endif
   if (workarounds_.disable_arb_sync)
     gfx::g_driver_gl.ext.b_GL_ARB_sync = false;
   bool ui_gl_fence_works = gfx::GLFence::IsSupported();
   UMA_HISTOGRAM_BOOLEAN("GPU.FenceSupport", ui_gl_fence_works);
 
   feature_flags_.map_buffer_range =
-      is_es3 || extensions.Contains("GL_ARB_map_buffer_range");
+      is_es3 || extensions.Contains("GL_ARB_map_buffer_range") ||
+      extensions.Contains("GL_EXT_map_buffer_range");
 
   // Really it's part of core OpenGL 2.1 and up, but let's assume the
   // extension is still advertised.
   bool has_pixel_buffers =
-      is_es3 || extensions.Contains("GL_ARB_pixel_buffer_object");
+      is_es3 || extensions.Contains("GL_ARB_pixel_buffer_object") ||
+      extensions.Contains("GL_NV_pixel_buffer_object");
 
   // We will use either glMapBuffer() or glMapBufferRange() for async readbacks.
   if (has_pixel_buffers && ui_gl_fence_works &&
       !workarounds_.disable_async_readpixels) {
     feature_flags_.use_async_readpixels = true;
   }
 
   if (is_es3 || extensions.Contains("GL_ARB_sampler_objects")) {
     feature_flags_.enable_samplers = true;
     // TODO(dsinclair): Add AddExtensionString("GL_CHROMIUM_sampler_objects")
@@ skipping 68 matching lines @@
   if (pos == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu