[gpu] Fix feature detection for ext_texture_norm16.

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 <stddef.h>
 
 #include <set>
 #include <vector>
@@ skipping 1294 matching lines @@
     validators_.texture_internal_format.AddValue(GL_RG8_EXT);
     validators_.read_pixel_format.AddValue(GL_RED_EXT);
     validators_.read_pixel_format.AddValue(GL_RG_EXT);
     validators_.render_buffer_format.AddValue(GL_R8_EXT);
     validators_.render_buffer_format.AddValue(GL_RG8_EXT);
     validators_.texture_unsized_internal_format.AddValue(GL_RED_EXT);
     validators_.texture_unsized_internal_format.AddValue(GL_RG_EXT);
   }
   UMA_HISTOGRAM_BOOLEAN("GPU.TextureRG", feature_flags_.ext_texture_rg);
 
-  if (gl_version_info_->is_desktop_core_profile ||
+  if ((gl_version_info_->is_desktop_core_profile &&
+       (gl_version_info_->IsAtLeastGL(3, 0) ||
+        extensions.Contains("GL_ARB_texture_rg"))) ||

[Ken Russell (switch to Gerrit), 2017/06/13 23:51:03]

This isn't necessary. Looking more deeply, GL_ARB_texture_rg was folded into
OpenGL 3.0, and is_desktop_core_profile implies a minimum of OpenGL 3.2.

       extensions.Contains("GL_EXT_texture_norm16")) {
     feature_flags_.ext_texture_norm16 = true;
     AddExtensionString("GL_EXT_texture_norm16");
 
     // Note: EXT_texture_norm16 is not exposed through WebGL API so we validate
     // only the combinations used internally.
     validators_.texture_format.AddValue(GL_RED_EXT);
     validators_.texture_internal_format.AddValue(GL_R16_EXT);
     validators_.texture_internal_format.AddValue(GL_RED_EXT);
     validators_.texture_unsized_internal_format.AddValue(GL_RED_EXT);
@@ skipping 414 matching lines @@
   if (pos == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu