Rollup merge of #66754 - estebank:rustdoc-capitalization, r=Dylan-DPC

Various tweaks to diagnostic output

src/librustc_parse/parser/item.rs

@@ -491,9 +491,12 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses a macro invocation inside a `trait`, `impl` or `extern` block.
-    fn parse_assoc_macro_invoc(&mut self, item_kind: &str, vis: Option<&Visibility>,
-                               at_end: &mut bool) -> PResult<'a, Option<Mac>>
-    {
+    fn parse_assoc_macro_invoc(
+        &mut self,
+        item_kind: &str,
+        vis: Option<&Visibility>,
+        at_end: &mut bool,
+    ) -> PResult<'a, Option<Mac>> {
         if self.token.is_path_start() &&
                 !(self.is_async_fn() && self.token.span.rust_2015()) {
             let prev_span = self.prev_span;
@@ -532,9 +535,11 @@ impl<'a> Parser<'a> {
         }
     }
 
-    fn missing_assoc_item_kind_err(&self, item_type: &str, prev_span: Span)
-                                   -> DiagnosticBuilder<'a>
-    {
+    fn missing_assoc_item_kind_err(
+        &self,
+        item_type: &str,
+        prev_span: Span,
+    ) -> DiagnosticBuilder<'a> {
         let expected_kinds = if item_type == "extern" {
             "missing `fn`, `type`, or `static`"
         } else {