onTouchEvent was previously incorrectly handled in GLSurfaceView; move it
to View so that it works properly with any of it's descendants.
This is done by reusing the existing setOnTouchListener implementation
and changing it to use GtkEventControllerLegacy which provides motion
events.
Technically some of the code is in WrapperWidget.c since every widget
calls wrapper_widget_set_jobject and we already have related code
there.
The current implementation requires a VA-API driver and a Wayland
compositor with YUV-buffer support. GNOME supports YUV-buffers
since the recent version 45 release
We decide between simple widgets which handles MEASURE_SPEC_AT_MOST the same way as
MEASURE_SPEC_EXACTLY, and complex widgets which handles MEASURE_SPEC_AT_MOST by measuring the content
implements android.graphics.Typeface (always uses default
typeface for now), one version of Canvas.drawText, one version
of Paint.measureText, and Paint.ascend
Using the C API provided by SkiaSharp's skia fork instead of using cairo
significantly improves performance. The API is also closer to the android
Canvas API, which makes the implementation more straightforward.
