Auto merge of #24547 - bombless:comma, r=pnkfelix

Closes #20616 
It breaks code such as <c64feb6341/src/librustc_typeck/check/method/suggest.rs (L367)>, so this is a [breaking-change], you have to add missing comma after the last lifetime arguement now.

src/libsyntax/parse/token.rs

@@ -173,6 +173,14 @@ pub enum Token {
 }
 
 impl Token {
+    /// Returns `true` if the token starts with '>'.
+    pub fn is_like_gt(&self) -> bool {
+        match *self {
+            BinOp(Shr) | BinOpEq(Shr) | Gt | Ge => true,
+            _ => false,
+        }
+    }
+
     /// Returns `true` if the token can appear at the start of an expression.
     pub fn can_begin_expr(&self) -> bool {
         match *self {