Add common GLFence::IsSupported() check

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"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "gpu/command_buffer/service/gl_utils.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
+#include "ui/gl/gl_fence.h"
 #include "ui/gl/gl_implementation.h"
 
 namespace gpu {
 namespace gles2 {
 
 namespace {
 
 struct FormatInfo {
   GLenum format;
   const GLenum* types;
@@ skipping 755 matching lines @@
     AddExtensionString("GL_EXT_frag_depth");
     feature_flags_.ext_frag_depth = true;
   }
 
   if (extensions.Contains("GL_EXT_shader_texture_lod") ||
       gfx::HasDesktopGLFeatures()) {
     AddExtensionString("GL_EXT_shader_texture_lod");
     feature_flags_.ext_shader_texture_lod = true;
   }
 
-  bool egl_khr_fence_sync = false;
 #if !defined(OS_MACOSX)
   if (workarounds_.disable_egl_khr_fence_sync) {
     gfx::g_driver_egl.ext.b_EGL_KHR_fence_sync = false;
   }
-  egl_khr_fence_sync = gfx::g_driver_egl.ext.b_EGL_KHR_fence_sync;
 #endif
   if (workarounds_.disable_arb_sync)
     gfx::g_driver_gl.ext.b_GL_ARB_sync = false;
-  bool ui_gl_fence_works = is_es3 || extensions.Contains("GL_NV_fence") ||
-                           gfx::g_driver_gl.ext.b_GL_ARB_sync ||
-                           egl_khr_fence_sync;
+  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");
 
   // 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");
 
@@ skipping 33 matching lines @@
   if (pos == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu