Rename AttrAnnotatedToken{Stream,Tree}.

These two type names are long and have long matching prefixes. I find
them hard to read, especially in combinations like
`AttrAnnotatedTokenStream::new(vec![AttrAnnotatedTokenTree::Token(..)])`.

This commit renames them as `AttrToken{Stream,Tree}`.

compiler/rustc_parse/src/parser/mod.rs

@@ -170,7 +170,7 @@ pub struct ClosureSpans {
 /// attribute, we parse a nested AST node that has `#[cfg]` or `#[cfg_attr]`
 /// In this case, we use a `ReplaceRange` to replace the entire inner AST node
 /// with `FlatToken::AttrTarget`, allowing us to perform eager cfg-expansion
-/// on an `AttrAnnotatedTokenStream`
+/// on an `AttrTokenStream`.
 ///
 /// 2. When we parse an inner attribute while collecting tokens. We
 /// remove inner attributes from the token stream entirely, and
@@ -183,7 +183,7 @@ pub type ReplaceRange = (Range<u32>, Vec<(FlatToken, Spacing)>);
 
 /// Controls how we capture tokens. Capturing can be expensive,
 /// so we try to avoid performing capturing in cases where
-/// we will never need an `AttrAnnotatedTokenStream`
+/// we will never need an `AttrTokenStream`.
 #[derive(Copy, Clone)]
 pub enum Capturing {
     /// We aren't performing any capturing - this is the default mode.
@@ -1464,11 +1464,11 @@ pub fn emit_unclosed_delims(unclosed_delims: &mut Vec<UnmatchedBrace>, sess: &Pa
     }
 }
 
-/// A helper struct used when building an `AttrAnnotatedTokenStream` from
+/// A helper struct used when building an `AttrTokenStream` from
 /// a `LazyTokenStream`. Both delimiter and non-delimited tokens
 /// are stored as `FlatToken::Token`. A vector of `FlatToken`s
-/// is then 'parsed' to build up an `AttrAnnotatedTokenStream` with nested
-/// `AttrAnnotatedTokenTree::Delimited` tokens
+/// is then 'parsed' to build up an `AttrTokenStream` with nested
+/// `AttrTokenTree::Delimited` tokens.
 #[derive(Debug, Clone)]
 pub enum FlatToken {
     /// A token - this holds both delimiter (e.g. '{' and '}')
@@ -1476,11 +1476,11 @@ pub enum FlatToken {
     Token(Token),
     /// Holds the `AttributesData` for an AST node. The
     /// `AttributesData` is inserted directly into the
-    /// constructed `AttrAnnotatedTokenStream` as
-    /// an `AttrAnnotatedTokenTree::Attributes`
+    /// constructed `AttrTokenStream` as
+    /// an `AttrTokenTree::Attributes`.
     AttrTarget(AttributesData),
     /// A special 'empty' token that is ignored during the conversion
-    /// to an `AttrAnnotatedTokenStream`. This is used to simplify the
+    /// to an `AttrTokenStream`. This is used to simplify the
     /// handling of replace ranges.
     Empty,
 }