Move parse_or_use_outer_attributes out of parse_expr_prefix_range.

This eliminates another `Option<AttrWrapper>` argument and changes one
obscure error message.

compiler/rustc_parse/src/errors.rs

@@ -2989,3 +2989,10 @@ pub(crate) struct ExprRArrowCall {
     #[suggestion(style = "short", applicability = "machine-applicable", code = ".")]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(parse_dot_dot_range_attribute)]
+pub(crate) struct DotDotRangeAttribute {
+    #[primary_span]
+    pub span: Span,
+}