Rename discardFramebufferEXT to discardBackbufferCHROMIUM to avoid collision with real discardFrame…

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/string_number_conversions.h"
@@ skipping 222 matching lines @@
 
 
   bool npot_ok = false;
 
   AddExtensionString("GL_ANGLE_translated_shader_source");
   AddExtensionString("GL_CHROMIUM_async_pixel_transfers");
   AddExtensionString("GL_CHROMIUM_bind_uniform_location");
   AddExtensionString("GL_CHROMIUM_command_buffer_query");
   AddExtensionString("GL_CHROMIUM_command_buffer_latency_query");
   AddExtensionString("GL_CHROMIUM_copy_texture");
-  AddExtensionString("GL_CHROMIUM_discard_framebuffer");
+  AddExtensionString("GL_CHROMIUM_discard_backbuffer");
   AddExtensionString("GL_CHROMIUM_get_error_query");
   AddExtensionString("GL_CHROMIUM_pixel_transfer_buffer_object");
   AddExtensionString("GL_CHROMIUM_rate_limit_offscreen_context");
   AddExtensionString("GL_CHROMIUM_resize");
   AddExtensionString("GL_CHROMIUM_resource_safe");
   AddExtensionString("GL_CHROMIUM_set_visibility");
   AddExtensionString("GL_CHROMIUM_strict_attribs");
   AddExtensionString("GL_CHROMIUM_texture_mailbox");
   AddExtensionString("GL_EXT_debug_marker");
 
@@ skipping 447 matching lines @@
   if (extensions_.find(str) == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu