emulate srgb format for generateMipmap

gpu/command_buffer/service/gles2_cmd_srgb_converter.h

Index: gpu/command_buffer/service/gles2_cmd_srgb_converter.h
diff --git a/gpu/command_buffer/service/gles2_cmd_srgb_converter.h b/gpu/command_buffer/service/gles2_cmd_srgb_converter.h
index f711fc8daddebe45c6fd96684902063b11d76499..75d946ee1c742094e7945e3556681e30318d46fe 100644
--- a/gpu/command_buffer/service/gles2_cmd_srgb_converter.h
+++ b/gpu/command_buffer/service/gles2_cmd_srgb_converter.h
@@ -50,6 +50,13 @@ class GPU_EXPORT SRGBConverter {
       bool decode,
       bool encode);
 
+  void InitializeSRGBEncoder(const gles2::GLES2Decoder* decoder);
+  bool srgb_encoder_initialized_ = false;
+  GLuint srgb_encoder_program_ = 0;

[yunchao, 2016/09/19 15:25:48]

This code snippet is not necessary. 

[yizhou.jiang, 2016/09/20 07:00:27]

Done.

+
+  void SRGBGenerateMipmap(const gles2::GLES2Decoder* decoder,
+                          Texture* tex,
+                          GLenum target);
  private:
   void InitializeSRGBConverterProgram();
   scoped_refptr<const gles2::FeatureInfo> feature_info_;