Rollup merge of #61087 - estebank:parsepalooza, r=Centril

Tweak `self` arg not as first argument of a method diagnostic

Mention that `self` is only valid on "associated functions"
```
error: unexpected `self` argument in function
  --> $DIR/self-in-function-arg.rs:1:15
   |
LL | fn foo(x:i32, self: i32) -> i32 { self }
   |               ^^^^ not valid as function argument
   |
   = note: `self` is only valid as the first argument of an associated function
```

When it is a method, mention it must be first
```
error: unexpected `self` argument in function
  --> $DIR/trait-fn.rs:4:20
   |
LL |     fn c(foo: u32, self) {}
   |                    ^^^^ must be the first associated function argument
```

Move a bunch of error recovery methods to `diagnostics.rs` away from `parser.rs`.

Fix #51547. CC #60015.

0 files changed, 0 insertions, 0 deletions