Revert of Add command buffer support for GL_EXT_texture_sRGB_decode

gpu/command_buffer/service/gles2_cmd_validation_implementation_autogen.h

 // Copyright 2014 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.
 
 // This file is auto-generated from
 // gpu/command_buffer/build_gles2_cmd_buffer.py
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 1198 matching lines @@
         GL_RGBA8_SNORM,
         GL_RGB5_A1,
         GL_RGBA4,
         GL_RGB10_A2,
         GL_RGBA16F,
         GL_RGB_YCRCB_420_CHROMIUM,
         GL_RGB_YCBCR_422_CHROMIUM,
         GL_RGB_YCBCR_420V_CHROMIUM,
 };
 
-bool Validators::TextureSrgbDecodeExtValidator::IsValid(
-    const GLenum value) const {
-  switch (value) {
-    case GL_DECODE_EXT:
-    case GL_SKIP_DECODE_EXT:
-      return true;
-  }
-  return false;
-};
-
 static const GLenum
     valid_texture_stencil_renderable_internal_format_table_es3[] = {
         GL_STENCIL_INDEX8, GL_DEPTH24_STENCIL8, GL_DEPTH32F_STENCIL8,
 };
 
 bool Validators::TextureSwizzleValidator::IsValid(const GLenum value) const {
   switch (value) {
     case GL_RED:
     case GL_GREEN:
     case GL_BLUE:
@@ skipping 296 matching lines @@
   texture_internal_format_storage.AddValue(GL_COMPRESSED_SRGB8_ETC2);
   texture_internal_format_storage.AddValue(
       GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2);
   texture_internal_format_storage.AddValue(
       GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2);
   texture_internal_format_storage.AddValue(GL_COMPRESSED_RGBA8_ETC2_EAC);
   texture_internal_format_storage.AddValue(GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC);
 }
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_VALIDATION_IMPLEMENTATION_AUTOGEN_H_