Attach YUV420 to RGB converter to GLContext

ui/gl/gl_context.cc

Index: ui/gl/gl_context.cc
diff --git a/ui/gl/gl_context.cc b/ui/gl/gl_context.cc
index 6d41cd0a571530ecf4ed2b3c903cb6ec457ec332..ac39011dd4fd5bc0834e06aa953f635d1934adb2 100644
--- a/ui/gl/gl_context.cc
+++ b/ui/gl/gl_context.cc
@@ -90,6 +90,10 @@ std::string GLContext::GetGLRenderer() {
   return std::string(renderer ? renderer : "");
 }
 
+gl::YUVToRGBConverter* GLContext::GetYUVToRGBConverter() {
+  return nullptr;
+}
+
 bool GLContext::HasExtension(const char* name) {
   std::string extensions = GetExtensions();
   extensions += " ";