1. htmlcanvaselement api: toblob

2. htmlcanvaselement api: toblob: `quality` parameter

3. htmlcanvaselement api: toblob: `type` parameter supports `"image/webp"`

4. offscreencanvas api: converttoblob

5. offscreencanvas api: converttoblob: `option.type` parameter supports `"image/webp"`