3179: Introduce AsMacroCall trait r=matklad a=edwin0cheng
This PR introduce `AsMacroCall` trait to help convert `ast::MacroCall` to `MacroCallId`. The main goal here is to centralize various conversions to single place and make implementing eager macro calls without further ado.
```rust
pub trait AsMacroCall {
fn as_call_id(
&self,
db: &(impl db::DefDatabase + AstDatabase),
resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
) -> Option<MacroCallId>;
}
```
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
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