remove @ from FontContextHandle in linux
remove SendableTextRun & remove @mut Font From TextRun&Shaper(Font),Font.shaper,
       fontfamily,fontgroup,render_context.font_ctx
remove @ fontcontext
Patch for macos
fix indent & some code
Merge pull request #1342 from ksh8281/remove_@_from_font_context

Remove @ from font context, remove SendableTextRun