Implement WEBGL_compressed_texture_es3_0 extension for WebGL 1/2

gpu/command_buffer/service/gles2_cmd_validation.h

 // 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.
 
 // Contains various validation functions for the GLES2 service.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_VALIDATION_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_VALIDATION_H_
 
 #include <algorithm>
@@ skipping 46 matching lines @@
   }
 
  private:
   std::vector<T> valid_values_;
 };
 
 struct Validators {
   Validators();
 
   void UpdateValuesES3();
+  void UpdateES30CompressedTextureFormats();
 
 #include "gpu/command_buffer/service/gles2_cmd_validation_autogen.h"
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_VALIDATION_H_