Allow creating GLImage-backed textures with glTexStorage2D.

ui/gl/gl_image.h

Index: ui/gl/gl_image.h
diff --git a/ui/gl/gl_image.h b/ui/gl/gl_image.h
index c29eff60d28dbafcefa0cedb07dd5546541b08d6..8a9b089041273773267686cebb1bb5b10c7cc579 100644
--- a/ui/gl/gl_image.h
+++ b/ui/gl/gl_image.h
@@ -97,9 +97,9 @@ class GL_EXPORT GLImage : public base::RefCounted<GLImage> {
   enum class Type { NONE, MEMORY, IOSURFACE, DXGI_IMAGE };
   virtual Type GetType() const;
 
-  void SetColorSpaceForScanout(const gfx::ColorSpace& color_space) {
-    color_space_ = color_space;
-  }
+  // Sets the color-space used to scanout from this image, if the image is
+  // used as an overlay.
+  virtual void SetColorSpaceForScanout(const gfx::ColorSpace& color_space);
 
   const gfx::ColorSpace& color_space() const { return color_space_; }