Expose mapExternalTexture extension to WebGraphicsContext3D

gpu/command_buffer/service/feature_info.cc

 // Copyright (c) 2011 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 <set>
 #include <string>
 #include "gpu/command_buffer/service/feature_info.h"
 #include "gpu/command_buffer/service/gl_utils.h"
 #include "gpu/GLES2/gles2_command_buffer.h"
 #include "ui/gfx/gl/gl_implementation.h"
@@ skipping 85 matching lines @@
 
 void FeatureInfo::AddFeatures(const char* desired_features) {
   // Figure out what extensions to turn on.
   ExtensionHelper ext(
       reinterpret_cast<const char*>(glGetString(GL_EXTENSIONS)),
       desired_features);
 
   bool npot_ok = false;
 
   AddExtensionString("GL_CHROMIUM_copy_texture_to_parent_texture");
+  AddExtensionString("GL_CHROMIUM_map_external_texture");
   AddExtensionString("GL_CHROMIUM_resource_safe");
   AddExtensionString("GL_CHROMIUM_resize");
   AddExtensionString("GL_CHROMIUM_strict_attribs");
   AddExtensionString("GL_CHROMIUM_swapbuffers_complete_callback");
   AddExtensionString("GL_CHROMIUM_rate_limit_offscreen_context");
 
   // Only turn this feature on if it is requested. Not by default.
   if (desired_features && ext.Desire("GL_CHROMIUM_webglsl")) {
     AddExtensionString("GL_CHROMIUM_webglsl");
     feature_flags_.chromium_webglsl = true;
@@ skipping 235 matching lines @@
 }
 
 void FeatureInfo::AddExtensionString(const std::string& str) {
   if (extensions_.find(str) == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 }  // namespace gles2
 }  // namespace gpu