fix hir for new block syntax

crates/ra_syntax/src/ast/expr_extensions.rs

@@ -9,12 +9,12 @@ use crate::{
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum ElseBranch {
-    Block(ast::Block),
+    Block(ast::BlockExpr),
     IfExpr(ast::IfExpr),
 }
 
 impl ast::IfExpr {
-    pub fn then_branch(&self) -> Option<ast::Block> {
+    pub fn then_branch(&self) -> Option<ast::BlockExpr> {
         self.blocks().nth(0)
     }
     pub fn else_branch(&self) -> Option<ElseBranch> {
@@ -28,7 +28,7 @@ impl ast::IfExpr {
         Some(res)
     }
 
-    fn blocks(&self) -> AstChildren<ast::Block> {
+    fn blocks(&self) -> AstChildren<ast::BlockExpr> {
         children(self)
     }
 }