Workaround for Mac video flickering

ui/gl/yuv_to_rgb_converter.h

 // Copyright 2016 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.
 
 #ifndef UI_GL_YUV420_RGB_CONVERTER_H_
 #define UI_GL_YUV420_RGB_CONVERTER_H_
 
 #include "ui/gfx/geometry/size.h"
 
 namespace gl {
 
 class YUVToRGBConverter {
  public:
   YUVToRGBConverter();
   ~YUVToRGBConverter();
   void CopyYUV420ToRGB(unsigned target,
                        unsigned y_texture,
                        unsigned uv_texture,
                        const gfx::Size& size,
                        unsigned rgb_texture);
 
+  // Workaround for https://crbug.com/611511:
+  // Destroying a GL texture object every frame will cause an implicit
+  // glFlush, which exposes a bug whereby incompletely-rendered compositor
+  // frames will appear briefly on-screen.
+  // TODO(ccameron): Fix the underlying but whereby inoppurtune glFlushes

[Daniele Castagna, 2016/05/17 19:29:37]

I think this patch makes sense by itself even if it weren't fixing the bug.
So, while this comment and TODO are useful, I don't think they're necessary
here.
Up to you if you want to leave them or remove them.

+  // cause incorrect rendering results.
+  unsigned y_texture() const { return y_texture_; }
+  unsigned uv_texture() const { return uv_texture_; }
+
  private:
   unsigned framebuffer_ = 0;
   unsigned vertex_shader_ = 0;
   unsigned fragment_shader_ = 0;
   unsigned program_ = 0;
   int size_location_ = -1;
   unsigned vertex_buffer_ = 0;
+

[Daniele Castagna, 2016/05/17 19:29:37]

nit: no need for the blank line.

+  unsigned y_texture_ = 0;
+  unsigned uv_texture_ = 0;
 };
 
 }  // namespace gl
 
 #endif  // UI_GL_YUV420_RGB_CONVERTER_H_