6950e428fe
When EGLImage extension is not available, SurfaceFlinger will fallback to using glTexImage2D and glTexSubImage2D instead, which requires 50% more memory and an extra copy. However this code path has never been exercised and had some bugs which this patch fix. Mainly the scale factor wasn't computed right when falling back on glDrawElements. We also fallback to this mode of operation if a buffer doesn't have the adequate usage bits for EGLImage usage. This changes only code that is currently not executed. Some refactoring was needed to keep the change clean. This doesn't change anything functionaly.